Help!!!! (clutch)

yesterday as i was driving home i noticed when i pressed in the clutch i could feel it rumbling under my foot & heard it kinda grinding in the back. i figured i'd get it home and take a look. well about a block before my apartment i pulled up at a stop sign and went to shift back into 1st gear. it would't go back into 1st or any other gear. also when i tried to put it in reverse (from a complete stop) it grinds..... any thoughts on what this might be???