Oil pump Shaft?

I just put in a new oil pump with new pump shaft, I might have put the shaft in backwards where the collar on the shaft is closer to the pump. I was wondering is this going to be a problem or should I be okay. The engine is already put back together.
 
It's not a problem until you pull the distributor out. Then the shaft will probably pull out of the pump with the distributor, then the collar will catch, and it'll fall into the oil pan. Don't pull the distributor if you can avoid it. :)
 
Thats good to here, I don't plan on pulling the dizzy any time soon. I have a windage tray but I didn't want to wait for itto put my engine back together. So I will probably drop the pan before I take the dizzy out so I can fix the shaft then.