By all means, lay the cards on the table... but focus on you feelings and troubles you're having at the moment, not the label... and focus on solutions. To the people you trust of course. You may quickly realise that a lot of people have experienced the same feelings in their life, at least to some degree, and a lot of people have not been diagnosed with anything, perhaps because the degree of troubles they experienced was not as severe as yours. Take their experiences as proof of concept, if something worked for them and you feel like it may work for you, even though you feel your problem is much bigger... it may still be worth trying.
This is where you can tap into the really valuable source of information of how people deal with what I call real life situations. I learned that everything in life exists on a spectrum, for diagnosed or undiagnosed. Except when you're diagnosed people, including & especially experts, tend to put you on the extreme end of the scale when you experience every minor or major hiccup which is not always appropriate. They're not doing it out of malice, it's a bit of a knee jerk reaction. I agree that extreme ends of the spectrum warrants\ some professional intervention but that does not mean that it needs to govern all aspects of your life. You can still implement practices of every day people into your life and only seek professional help as "extras".
This may all sound like a bit of a fluffy philosophy but it is derived from my personal experience and I will give you very specific examples. I was diagnosed with bipolar 1, severe... according to psychiatrist, whatever that means (several hospitalisations, psychotic manic episodes as well as severe depression etc.). I had weekly appointments for many years where I was open and direct about everything that was happening in my life as everyone encouraged me to be (boyfriend/husband, psychiatrist, friends). I shared daily struggles with all of them. Everything from benign experiences of interactions with coworkers to real fucked up stuff of delusional grandiose thinking. My psychiatrist was really into putting my husband as a trusted person into the equation. But that turned out to be detrimental to me... as everyone started beating to the sound of the same drum. Every minor obstacle became reason for concern and major intervention. That's not what I expected or wanted. For example, I'm an outgoing direct person, young and not very tactful. As such I said & did many things which could have been handled better in a work/university situation... yet anything I did was always palmed off to me having this terrible condition called "bipolar" which magically excused me of any accountability & responsibility in the eyes of others... yet somehow deep down inside of myself I knew that was me and not all of me could be explained by a medical condition. What I learned through this experience was that my psychiatrist was very good at managing critical situations where I was really loosing control but unfortunately he had the same approach with all minor issues as they were seen as risk that needed to be mitigated. I learned that I am in my nature a passionate, temperamental & slightly eccentric person, I feel and react to everyday situations deeper than most people and this is an aspect of my personality rather than a result of an illness. I can be chaotic but goal oriented at the same time. In the process of "growing up", even though I'm now in my late 20s I needed to learn how to handle myself. I organised wild parties, told people to shut the fuck up in a rather rude way, went on on eccentric self-promoting binges, ambitious as fuck, made enemies as well as friends for life etc. For periods of time all of this was managed as an illness and made me miserable, I felt obliged to hand over my life to others to judge what was normal and what was not. If I didn't sleep for a day I was one foot deep in being manic, if I felt "lazy" I was one foot into depression.... honestly, fuck this shit. I am the captain of my soul, the master of my faith. I may not be the "standard" out of the box person but I am who I am and everything I did in my life was a valuable experience and as such, even though I would have changed some things if I got the second chance, I regret nothing. I called it quits when I was experiencing what most would call a depression... I was down, not running on fully charged batteries for about 6 months and every week I got a script for new pills even though I was telling everyone I was merely having more sleep & rest, as my body instructed me, and I was still functioning close to an average person, albeit I had to struggle to achieve that. Yet it was "pill this"/"pills that", you need therapy, you're traumatised etc etc. If I followed their advice all would magically be better... but would it be better because of their advice or the pills I'm not so sure, it didn't quite work for me in the past. I saw my coworkers come to work tired on some days because their kids had tummy flu over night and kept them up, cause they inured themselves playing footy over the weekend or because they had too much to drink... they all handled it in the same way. It's okay to whinge for a while and harden the fuck up as they tell you. My coworkers took a day off for not feeling perky... and I started doing the same. I learned to accept that I'm not a super machine all the time & not everyone likes me all of the time. I make mistakes and that's okay... everyone else does too, nobody is perfect, yet we still tolerate each other. I started to pursue my crazy hobbies and vent the "manic" energy through acceptable ways, go to crazy parties and get wasted... and to be honest, I felt shit like everyone else when I overdid it... but hey, that's life. Life became life for me again, not a terrible disease... and as such I accept the hard parts, bitch about them as anyone else would and revel in the good parts, go nuts and enjoy it. Life has been full of ups and downs since then. The risk of experiencing major shit is still out there and if it happens I'll happily swallow some pills for my comfort... but to let it govern my life, no fucking way.
So whatever they tell you, focus on your functioning rather than a label/symptoms and as cruel as it may sound, toughen the fuck up like everyone else. If need be, you can always seek professional help but never let that be your first priority or think it's your weakness. Good luck!