Engine trouble- Plummeting oil pressure

Dang, I am glad nothing blew up!

UPDATE 2: I replaced the fuel pump. The old one had some visible cracks on the diaphragm but they didn't look like they went all the way through. I also pulled the top off the carb and checked the needle and seats. Checked the floats too, they seemed fine. Didn't see any metal in the oil or filter. Fired it up and had 40psi oil pressure. Haven't taken it out yet but I am thinking about running it for 20 minutes or so and keeping an eye on it before I drive it.