No, if you are telling the truth what you have there is one incredible Beldum. Do not reset the game, get a Ditto (don't care how) and breed that SOB for better natures. You do that and you'll have one helluva Metagross.
Also, did you raise it's level any? I ask because at low levels it is very difficult to get an even somewhat accurate IV value calculation. I'd raise it up till it's a Metang at level 25 and then calculate IV's, just to be on the safe side.