I made (2) cakes, and after I covered them in fondant, they got a bulge on the side from the icing inside (I am assuming). What am I doing worng???? HELP!

What kind of filling are you using? If your filling is too runny you may need to use a stiff buttercream dam to prevent the filling from oozing out.

You need to pipe a dam around your cake to stop the filling oozing out, then you need to let it settle. Leah_s has a system where she places a tile on top of the cake so that the any icing which wants to bulge, bulges before you buttercream/fondant them. I can't find the thread with the instructions on them, maybe someone has it saved?