Was this a LSD flashback?
First of all I have only taken LSD for the past year and have been on a voyage of self-discovery for the past 9 months where I'm finally getting to know my true inner self (I like me now

) I have been careful about tripping during this time, only taking LSD occasionally, in small doses and building it up when I do. 3 weeks ago I discovered a "new" emotion for me, of being "at peace", where nothing could phase me, and while I had no visuals (except for during a quick NOS boost) I seemed to completely plateau - my mates who are more experienced thought I had serotonin-ed out
I had an "intense" trip about 8 days ago where I couldn't get comfortable for hours. In hindsight I shouldn't have tripped as a lot of small things were upsetting me, especially as it turns out the blotter was very strong, luckily I only took half a blotter (talking to others who are a lot more LSD experienced as me told me later that 1/2 had wiped them out after 4 to 5 hours and they went to bed)
I cant call it a "bad" trip, but it definitely wasn't a good one. I had massive temperature drops where I was wearing 3 layers to keep warm, while most people were in tee-shirts/shorts. I felt as if my upper arms were being squeezed into my body and my ears were as if they were trying to pop at the same time with slight muscle contractions, with paranoia that I'd loose my friends and be left alone. After about 6 hours I finally started getting my head into a space where I could go and sit on my own (keeping my friends in sight), control my breathing and loose the feeling of panic and finally get warm.
Last night, after chilling with friends for the first time in a week and smoking grass and having 3 beers with one of the best giggle fits in years (I'm a daily pollen smoker mainly, but do like grass as a treat) I felt that I needed to get home as I was wasted. I walked out, went to a shop for some sugar munchies and as soon as the sugar hit me I had a sudden feeling of panic. The same shivering cold, upper arm squeezing, ear poping feeling that I had during the trip kicked in. I needed to get home quickly. I tried walking faster to warm up, but just kept getting colder and shivering more. Eventually after about 10 minutes I started figuring out things, started controlling my breathing and realising my muscles were all in contraction started to relax the muscles. After another 10 minutes I was fine again, got home and had a great sleep.
I have been improving my diet over the past few weeks where I can now say I eat healthly, though do get massive munchies, and am going through a lot of changes in my life, so the odd mood swing and slight panic attack are nothing new to me, but it was the intensity of the one last night and the similarity of the feelings during the "intense" trip 8 days ago that freaked me out a little.
I have had flash-backs before where suddenly I remember something, or figure out why I was doing something that didnt make sense up until then, but never going back to a same emotional state.
I know I'll never figure out exactly what happened, but any advise would be appreciated just to help me along the way.