I am a little confused too. You say you have low oil pressure. I don't see where you have an oil pressure reading. Maybe I missed it. It takes heat for rings to seat and it sounds like you haven't run the engine hot. There is no sense in even checking compression before you seat the rings. I usually put a piece of cardboard in front of the radiator to keep the temp up and then vary the rpm. Too much oil will cause the oil to foam and you may have gotten air in your lifters. I would drain all the oil, let it set a day or so with the plugs out, put in fresh oil and start all over. It will probably be fine.