Doctor started me on 10mg, which didn't do anything. Without their recommendation, I tried 20mg, but still nothing. Should I go back to 10, and should I mention this to the doctor?

My doctor started me on 10mg of Vyvanse, probably because she's worried about how I'd handle stimulants (I have a diagnosed "anxiety disorder"). I've been taking it for a few days, but have not felt anything, including side effects. This morning I tried taking 2 pills, totaling to 20mg. Again, I feel the same as I always do. This time I have noticed very minor side effects but nothing else. I'm still struggling with my usual ADHD symptoms.

My next appointment with the doc is next week. I'm not sure if she'll increase the dose, or by how much. Would it be worth mentioning to her that I did try 20 and nothing happened? I know I should probably go by her recommendation and titrate up bit by bit, but I guess I'm frustrated knowing that it may not work for a few more weeks as we gradually increase. Should I just go back to taking the 10mg for now and see what happens?

Has anyone else started on the lowest dose with no effects?