to PC.

I think that's a common response - being a teen is tough because people just assume. And likelihood is your friend is also around the same age? They might not have the life experience to understand. I'm glad you're getting help. Dysthymia can really affect your life but it can get much better with treatment =)

are you going to a therapist? are you trying medications?

Have you tried doing aerobic exercise (even just jogging around the block) for a total of 20 minutes at a time, 2-3x a week? For some people this can improve your mood by quite a bit if you do it regularly. It's free, and easy to do and can even be fun. You could do this by playing basketball with friends, or whatever as long as you get your heart rate/breathing rate up =)