You may have gotten this all fixed by now, but here is my guess:
When you hit the puddle and the engine stopped, it may have had enough water in the clutch housing (bell housing) to have knocked loose some of the grease and crud that is always in there. If some of this fell into the space between the clutch pressure plate and the friction disc, the crud may be keeping the friction disc from coming to a stop when you put the clutch pedal down.
If this is the case, you would be able to put the car into gear, then start it up with the clutch pedal depressed. It might want to start rolling, but hopefully it would stop if you pressed on the brake, at the same time keeping the engine from dying. This takes three feet, or a stick in your hand pushing the gas pedal down.