We accidentally painted the ceiling with the paint instead of starting with the primer. (The cans looked alike and it was super late- first mistake.) Should we go back over the ceiling with primer, then paint again? Or can we just do a second coat of paint and be done?
At this point applying primer won't do any good, it will lay on top of the ceiling paint and not adhere to the actual ceiling surface. If everything is looking good then don't worry about another coat, but if the ceiling needs another coat of paint then go ahead and just apply another coat of ceiling paint.