Adderall Question

I am 19 years old, and just started to take adderall. I started with 5 mg twice a day. It seemed to be working ok, and I was feeling pretty good about it. I then took 10 mg twice a day about 2 or 3 days later. I stayed on that for a while because it seemed like it was working well. when I was about a week into taking the adderall I Got a terrible head ache and had to stay in bed for a day. I started back up on the medicine a few days later and everything was going fine. My docter them told me to take 15 mg twice a day. Which I did today. I felt about the same as when I took 10 mg except about 5 hours after taking 15 mg I felt very strange. I felt loopy, not really a dizzy feeling, but more of a light headed feeling. could this be my body that is trying to adjust to the medication or should I stop taking this all together. I am kind of nervous because I have never felt like this before. It is hard to describe the feeling but it just feels very strange and I do not like it at all. Any advice would be awesome. It just seems weird to me that I am having this affect after the drug is done working. Thanks in advance to anyone that responds to this.

I KNOW WHAT U MEAN-- ITS SO WEIRD
YOU FEEL THE WEIRDNESS LIKE 5 HOURS LATER AFTER ITS BEEN GREAT UNTIL. SOMETIMES ITS A SHOOTING PAIN IN UR ARM AND A HEART PANIC WHILE TRYINGTO GO TO BED I DONT GET IT!! its prob all mental!