I started taking 20mg of adderall rx about a month ago, the first day it made my head hurt and made me feel really sleepy. The second day it was okay my head didn't hurt and I didn't feel hungry like my stomach didn't grown once except when it wore off around night time. Didnt help me focus at all I felt the same without it just that it didnt make me hungry.The second week still took it even though it didn't help me focus and today my heart rate has been really high since the morning after I took it I don't know what this means and if its normal. It's 9:12 pm rn in bed and my heart rate is just pulsing really rapidly I felt okay through out the day except afterrible I donated blood in school idk if that could affected me in anyway but kinda worried help and advice would be very much appreciated.