the older MAOI drugs are more effective but have more side effects in general which is why SSRIs are popular (aside from making pharm companies shit loads of money). You also have to be careful of what you eat and which drugs you use.
For OP: Some people with ADD and anxiety get relief from a more smooth stimulant like dexedrine or even methamphetamine (not the street drug but the medication). For some people that sorts out the anxiety, especially social anxiety. Mixing stims and benzos will lead you down a terrible path possibly but if you really only use a therapeutic dose of a benzo as needed and are not dependent on it then i don't see an issue. In fact studies show that benzos maintain their efficacy as anxiolytics even long term if they are not abused. I don't think most people realize how crippling anxiety is, especially panic attacks. I've had many people tell me it's all in my head, it's not like i'm going to die and things like that. It's incredibly frustrating as i'd rather die than have a panic attack anyway.
I think it's important to develop social skills and to be well socialized and the only way to do that is to get out there and mix with people, interact, make mistakes, embarrass yourself, face your fears and always challenge yourself. You have to constantly push yourself out of your comfort zone and that is what therapy will teach you. Breathing techniques can only do so much for me, sometimes i have panic attacks that last days, especially since i am and have been a benzo addict for years now. Best advice i can give is to use a short acting benzo when you have a panic attack and to get therapy so that you can go to class without panicking. If all else fails there are still more options. I felt so hopeless last year when i detoxed from benzos and opiates. I ended up relapsing anyway but this time i went to therapy and dealt with a lot of things and along with using benzos as needed, i improved my life greatly.
Things aren't perfect now as i'm again stuck on etizolam instead of a reg. benzo which presents a different problem altogether but medication isn't necessarily the answer, definitely exhaust other options first, like exercise, diet, sleep hygiene, self-help, pushing yourself into uncomfortable situations.
The thing that actually made a difference for me was to embrace the anxiety, feel it, take it in, see it for what it is, ask yourself, "why am i feeling anxious?" you may not have an answer but there's an answer to that question if you dig for it. Basically what i am describing is mindfulness, which is the only thing that actually helped my anxiety. Look into it and see how it has helped others. I am a relatively social creature now and still deal with anxiety of all sorts but i can say i'm in better shape than i was a few years ago.
I also wouldn't try seroquel for anxiety; it's terrible for anxiety, it causes anxiety and dysphoria. I am prescribed seroquel for anxiety and only take it for come downs, and it's still a terrible drug for anxiety. The only reason it is prescribed for anxiety is for money. I have never seen a single study showing the efficacy of seroquel as an anxiolytic. It may be a great medication for schizophrenia but it will make you into a zombie if you're treating anxiety.