sag

Is it okay that I shoved some plywood up under my bumper to hold it up better? This is a top view of the inside edge of the middle of the bumper. It does seem to help a lot with sag. Yes? No?

OK so i bought my P5 about 2 months ago and I noticed this issue. I'm just getting around to figuring out what's wrong. at first look it seems like my drivers side is really low. the distance between the tire and fender on the drivers side is about 1" and almost 3.5' on the passenger side. so...