Cam wiped out, what the hell did I do wrong?!?!?

I was just wondering how long after your original breakin, before the lobes were damaged?? were you driving it?? I have a flat tappet, Comp cams (thumper cam) in my engine that i just had built, ran it like your supposed to per breakin,( i used comp cams brake in oil) and i have about 20 miles on it now, runs real strong, no noises, do you all think i am ok ?? or is there still a possibility that my cam will self destuct??