Lost channels 2 - 47 on basic cable connection

I was watching tv in the bedroom which is just a basic connection from the wall to the tv ( no box) and the channel went fuzzy like there was interference and then the screen went blue. Ever since then I have a blue screen on channels 2-47 but a perfect picture on channels 48-70.  I have disconnected the coaxial and reconnected at both the wall and the tv. My son has the same set up in his room and he is getting all channels perfectly.