The issue is you have no idea now to stop a move so you just come onto here and call it over powered. These threads are ridiculous. How the hell is this a serious thread? That guy was probably just messing around. Just go into training mode and set the dummy doing head butts and figure out a way around it. And no, shinprukens and low forwards are not the answer to headbutts.
On a side note, stop throwing those hados at that range. If it was a gief that wasn’t goofing around with headbutts, you would have lost even faster. He could have exghed you a million times over or simply just landed and SPD/Supered you. So yeah… learn the match up and quit your whining.