Two many people working on a project... I am refinishing a wood floor. We sanded it, stained it and I used a water based polyurethane for the finish. I had put two coats on but did not have the finish I wanted, so back to the store and picked a 3rd gallon of polyurethane... this was oil based (cans are almost identical)... My husband said he would put the third coat on.. I left. I never looked at the polyurethane. I would have noticed that it was not milky like the water based. We put the oil on top of the water based poly... Do we need to competely refinish the floors... resanding, restaining everything? or will this oil based polyurethane finish be ok.... It is shiny.