My bike is my main transportation, no rain or snow usually stops me (there was one day snow did this past winter and 9 days strepthroat kicked my ass in January).

Other than the road being a bit more slick, I've no qualms riding in the rain - I'd prefer the fixed wheel under me than a freewheel to be honest. This goes for snowy/icey conditions too. Roads get the same kind of slickness regardless of what bike you ride, just watch what you ride on/over (metal, leaves and painted lines = potential danger) and you'll be fine.

Sounds like you've not got enough grip or something weird happened.

Get a jacket, rain pants, booties and some fenders and you'll be giddy as all hell </fred car free cyclist>