Is it the clutch? HELP!!

I was racing at the track tonight and had 2 good runs on my third one I misshifted and lost all power to the wheels. The engine starts and sounds just fine, the shift linkage works but the car wont hold any power. 3 Weeks ago I just had a heavy duty clutch installed and it has felt strange since It was installed. Do you think it is just a problem with the clutch or is it the transmission?