I was prescribed Adderall IR for Adult ADHD, and it works, but I have some weird side effects?

Hello, I was recently diagnosed with Adult ADHD, and when I take the Adderall, it's like night and day: I used to be hyper-active and jitter a lot, and I could not sit still (at work, school, etc), I could not focus on things for a long period of time AT ALL, I'm 19 now, and I have NOT done homework since third grade (wasn't diagnosed because I went to a Catholic school with 50-70 year old nuns as teachers, ADHD? Yeah right) . I scored 2030 on my SAT, but managed to leave high school with only a B-/B average. Now that I take the Adderall, I don't jitter, I can EASILY sit still, (I wrote a 6 page paper without even getting up! It amazed me). My boss commented on my better work ethic, my better focus and my new-found ability to sit still! I have two issues with Adderall: the fact that it wears off within 2.5-3 hours, and the side effects: the ones I can stand don't bother me at all: appetite suppression (I just eat in the morning before and at night), and dry mouth (I just drink more water). The side effects that bother me actually set in after the Adderall wears off (sometimes, very rarely during) those side effects are: anxiety (I feel anxious for no reason, never happened to me before!) paranoia (I always check behind me, randomly, in fear, then realize it's the Adderall wearing off), and the worst one is the muscle tension! All of my muscles feel pulled extremely tight (not pain, exactly, just tension).