Hi Candybear,
You've raised an important issue. I think that everyone with any sort of mental health problem tends to worry about stigma at work.
Your boss sounds cool though. Maybe it would set your mind at rest if you could have an evaluation meeting and clarify any worries. We do that here in the UK, but I don't know if you have the same system in the US.
Above all, I would say to go easy on yourself. It sounds like you have an interesting job and I'm sure your good at it.
Good luck