Yeah, "just a bit" ? You surely should not have cut off all the roots if the plant had healthy growing leaves on top. A tuber would maybe grow again if it had gone dormant and was not supporting any leaves. Only time will tell.
Luckily, those plants are not hard to come by. Go get yourself a nice new one, put it in a pretty pot, and forgive yourself.
Planticide . . .
Trust me, we've all done it.
Welcome to ATP, and, um, maybe ask us for advice before you cut next time?