i'm 40 years old with ADHD. I have been taking 27mg of Concerta for 8 days. the first 6 days were awesome, no side effects at all (well besides loss of appetite) Yesterday started feeling side effects. I thought I was getting sick but now that I'm reading about everyone's side effects, that's what I'm feeling. Very bad headaches, stomach hurts at different times of the day, twitching muscles in my arms, heart pounding rapidly...etc.. I absolutely love that it helps me concentrate for hours and hours at a time with college.. Will these side effects go away after a few weeks? Please help me!!!!!!