Adderall working or not?

Okay, I was prescribed Adderall a few weeks ago, maybe 2 weeks ago? Anyways it is 20mg (I think rapid release?) and I am supposed to take it twice a day. Since I started taking it the only effects I feel are a kind of a nasty/dry taste in my mouth and I don't really every feel sleepy. Other than those 2 things I don't really notice much of an effect. I'll be honest the reason I started taking Adderall was to try to get the focus to study the subject I have always wanted to be extremely good at, programming. However since I started taking the drug I have only programmed maybe 2 times each session was about 8 or 9 hours of programming? But the issue being is I cant tell if it is helping me focus or if that was just me thinking it was working? I'm supposed to visit my doctor again here in another 2 weeks, and tell him what side effects I have been feel if any and inform him if I think it works... Problem is though I really don't know if it works or not and I could really use someone advice on that. Reason I think it doesn't work is because my Girlfriend tried Adderall recently and she was like "Wow I felt so focused on every task, and when I was taking my test I felt smart...". I don't feel smarter when I take it nor can I tell if I am more focused or not... Anyone have any ideas? Time does fly on Adderall though.

Thanks for taking the time to read, and reply if you replied.