I've never taken a dance class before ... but I definitely have had my fare share of sports related injuries. If you're never done dance before then you were most likely using and straining muscles that are not use to being used like that. Make sure to stretch A LOT before and after your next class. It is normal to experience a lot of muscle pain afterwards, but if its gotten to a point where you physically can't walk then i agree, you should see a doctor about it.

Ice might help too ... it will calm the swelling and ease the pain a bit too - or it should!

Hope everything works out
Jacq