Maybe some debris got into your carb from running the tank dry and either stuck your needle valve open or clogged a jet or something? I would clean the carb and flush the cylinder by pulling the plug and rolling the bike so the motor turns over a few times with the plug out (make sure there is no spark or flame around that could ignite fuel coming from the cylinder). Then clean the plug or install a new plug and see if she fires. You might also check the fuel filter that is in the top of the fuel valve, but since you said the plug is wet I would be leaning toward your needle valve being stuck open and causing your motor to flood.
Good luck....
