Depending on the quality of the supplement, fish oil and B vitamins were definitely not the cause of your problems. Even your doctor will recommend fish oil. You do want a good quality supplement to make sure it isn't contaminated, however, so to all, be careful when purchasing supplements, especially those sold only online or by direct marketing. But creatine can be dangerous if consumed in excess. Bodybuilders use this, and it can be effective for some of them, but bodybuilders will usually take anything -- they're worried about their looks, not their health. It certainly isn't necessary for anyone to take. And maybe one thing you need to do is stop worrying and start just accepting who you are. I know you say you don't have time for therapy -- a very typical avoidance. If you do believe you have an anxiety problem, as I've said before, therapy can be useful to prevent it from becoming chronic problem. But whatever you choose to do and however you choose to do it, you seem to be doing better in real life than in the one you sometimes present. It's good to focus on the good as well as the not so good. Peace.
Well the weed and creatine probably aren't helping, and aren't good for you either. Just ask your mom! You were right to get off the supplements, IMHO they don't really make any difference except in your wallet. You've somehow lost your confidence. One way to get it back is by going out of your way to be in more situations that make your nervous, so that you can gradually regain your confidence. The more often you succeed in doing things like introducing yourself to a room full of fellow students, the more your confidence will return. What you DON'T want to do is the opposite by avoiding such situations, because you will convince yourself that you CAN'T handle them which will only make things worse. Seek out social situations that make you nervous, and eventually the anxiety will lessen. Good luck!