There's nothing wrong with seeking a second opinion! I got 3 opinions because the first 2 said the exact opposite of each other.

First opinion said yes ADHD, no bipolar.
Second opinion said no ADHD, yes bipolar.
Third opinion said both ADHD & bipolar.

I actually think it's *good* to get multiple opinions, but do make sure that whomever is giving you a 2nd opinion has some documentation or something for your original Dx. It's good to have the person analyze the other doctor's decision.