Yes, some of us have bipolar and comorbid ADHD. I'm one of them, and medicated for both; with a mood stabilizer, an antipsychotic, and a stimulant.

The Ritalin test is a good one. If you have ADHD it'll likely calm you down, allow you to focus, and generally change the way you see the world in a good way. If you don't have ADHD, it'll be like rocket fuel and you'll feel like a squirrel who has just shotgunned six triple espressos.

Keep us posted.

ETA: Don't worry about the psychiatrist dismissing the possibility of BP because you're too high-functioning. Coming from another high functioning individual, I can guarantee that it's possible to be high-functioning, BP, and ADHD. I'd suggest you find another psychiatrist, and have your GP connect with them before your first visit. Doctors tend to usually take other doctor's thoughts seriously, especially when they have as long a history with you as yours does.