Is My Clutch Going Bad?

My car is a 2001 Volkswagen Passat. 1.8T with Manual Transmission..
Well i lent my car to someone for a couple weeks.. When they asked to borrow my car knowing it was Manual i thought they were comfortable with a stick shift.. but today when i got the car back, and he picked me up and drove me around, i noticed he wasnt strong at all with a stick shift... The car bucking, stalled once, and when launching you heard the clutch. I was like my clutch was going through this abuse everyday for 2 weeks... So when i drove it, i noticed some of its get up and go kind of got up and went... I know its only a 1.8 Liter 4 cylinder engine but it was still a very peppy car... But it feels like to me that some of that Pep is gone... Does that mean that the clutch is worn or its not catching or something like that? The engine doesnt race or anything when you give it gas and it moves but not as quick on the launch as before... I don tknow, maybe its my imagination... Is that a sign of the clutch being worn out? Is my clutch on its way out?