this happened to me not long ago, unfortunately it was almost the worst thing that could have happened. The timing belt snapped, and the pistons weren't too happy about the valves being in their path. They got all pissed (pun intended) and bent all the little happy valves sending them straight to hell.

First thing that I would do is get on your knees and pray that this didn't happen to you. Then check....The easiest way to tell is by opening the oil cap and looking into the valve cover with a flashlight. Get somebody to try to start the engine while you look. If you don't see your cams moving then your royally screwed. you can also check by taking the distributor cap off and making sure the rotor is turning while somebody tries to start the engine.