Why isn't my Adderall XR doing anything for me?

I'm a 29 year old female. I was diagnosed with ADHD at the age of 11. My parents choose to take a non drug approuch to my what they thought of as a learning disablity. I was successful in high school and wasn't till college that my ADHD started to effected my day to day life. At 25 I went on Strattra. The Strattra worked great for me. My insurence resently raised my copay on the Strattra so I asked my doctor to change me to something that would be less. I was put on adderall XR 20mg. I just compleated my second month on the medication. The problem is I feel NOTHING. I could take a vitamin and get the same effect. I have been unable to concentrate at work. I'm getting up twice and much. I find myself talking nonstop. The only thing I have noticed is that I have been sleeping great, I normally suffer from insomiea. My docotor looked at me like I was lying when I said it did nothing for me. Is what I'm experenceing normal? Why isn't it working for me? What should I do?