This has been discussed ad nauseum in other threads (search "Prom" for examples), so I'll limit myself to saying that what you're describing is not even close to being a tuxedo or resembling any sort of proper formalwear. You are of course free to wear what you want and prom may involve motives other than looking good in classic menswear (plus it's prom so someone will wear something worse). I don't mean to sound harsh, but you should at least know how awful this sounds so you can make an informed decision. People your age often don't realize that sometimes doing things correctly stands out just enough and looks better, until they look at their prom photos ten years later and wonder what the hell they were thinking.
+1 to these.