Don't do it mate. I'm 24 and have been smoking weed daily for years, have done LSD a lot, ecstasy. Adderall/amphetamine addiction is a different beast.

Got addicted to it in my final semester of college. First of all, it fucks up your teeth since not only are you constantly clenching, but I read that it also restricts the blood flow to your gums, which causes damage as well. Eventually the comedown from addies also gives you horrible headaches and make you feel like shit since you never have an appetite and exhaust your body. Next thing you know, you're taking addies to do basically anything -- go to work, school, hang out with friends.. And better believe your friends/family will notice your tweaky behavior eventually.

I was addicted for half a year before my script ran out and I quit. I quit in June of this year and its been my first experience with real physical drug addiction (not weed). I had pretty bad mood swings for a couple weeks, and also my heart was hurting and beating abnormally sometimes when I took adderall. Ever since I quit, I feel a lot better, and I also get a lot more cardio since I'm paranoid about my heart now.

Also.. I got really fucking good at guitar in that 6 months I was addicted. I remember spending 10+ hours a day just sitting there, playing.