Please help!! no oil pressure after oil change!!

Well the good news is that you can pull the pump and replace it externally.

You might have a crack in the pickup tube, leaking air.

Cranking it with the filter removed was a good plan......it removes head pressure (resistance) to the pump and renders the "easiest" pumping condition.

You might pull the dist. gear and see if you can prime with a drill.

There's an oil ring up in "on" the pump snout in the engine. These can fail