clutch sticking to floor when held down.

I can shift just fine and everything, but if i hold the clutch down for anything over about 2 seconds, it will stick. I can deal without the downshift by just poping it in neutral, but it is a real pain when trying to go in reverse. Why is the pedal sticking? I have to pull it out with my foot. It was fine one day, then the next day, i woke up and it was doing that.