Easiest way to prime the oil system is to chuck up the correct size socket and a long enstension on a drill motor. The socket is slipped onto the pump drive shaft, then you just run the drill until you feel the oil system pressurizing. You will hear this in the drill motor speed. I usually run it for several minutes, but that is probably overkill. Use some tape to hold the sockets and extensions together so that they don't come loose and fall into the oil pan.
It is possible that the pump died when it was run with water in the system.
Here's my suggestion...
Put the filter back on and prime the pump for a fair amount of time. I have had to run the drill motor for quite a while before starting to get pressure from the pump. Once you get oil flow through the pump, pull the filter to verify that you are getting some oil flow. If the filter has oil then give the car a start, you should be ok. If the filter is still dry then there is either an obstruction in the oil system or the pump has taken a nose dive.
Good Luck