Hi and welcome to the forum.
I'd bet that it's just a bad connection or sending unit. If you really had zero oil pressure you'd know very quickly after starting the engine I would think. Having said that, it needs to be fixed whatever it is.
Best of luck
Rick, Nancy, Peanut & Lola our Westie Dogs & Bailey the Sheltie.
2007 Itasca Ellipse 40FD