Adderall XR and headache

I was finally diagnosed with add last November. The doctor tried me on Straterra. It made me tired all the time and emotional. Next we tried Concerta. That made me agitated and irritable, So then we finally got around to adderall. It worked, yay! 10mg 3xday did nothing for me, so the next time I went to my pdoc I told her. So she upped my dosage to 20mg in the am, 10mg at noon, and 10mg in the pm. I did not understand this. I tried this for a few days and guess what? I did okay in the am, but the noon and pm dose were useless. So I took it upon myself to just go ahead and take 20mg 3xday. Only side effects were dry mouth and appetite reduction. I ran out a week early, but no biggie, I was prepared for the consequences,
So the next time, I see my pdoc (new one this time), I tell her what I'd done and I felt that 20mg 3xday was right for me. She recommended adderall xr30mg in the am and 20 regular adderall in the pm. I decided to go ahead and try it, figuring xr is the same stuff in a time released form.
Oh how wrong was I! Side effects started with headache, then drowsiness to the point I had to take a nap. I've been becoming more and more emotional and irritable since I've been taking it (2 weeks now).
Earlier tonight I had an episode that could have turned into a bad panic attack. Luckily, though, I got to my clonezapam before I got too far out of control.
I just don't understand how the (supposed) same drug in a different form could have such different side effects. I was going to continue with the xr, hoping the bad side effects would diminish in time, but after tonight, I think I will flush them.
Has anyone else had the same or similar experience?