Help! Paint and Primer peeled off the wall!?

I am painting my son's bedroom, which previously had murals on it. To be safe I sanded down the uneven parts and put a gray gripper primer on the wall made specifically for dark and bright colors. The paint scheme he has going in his room is a complicated red/black combo (stripes, checkers etc). Both the paint and primer are for active rooms (kids' rooms), semi gloss and are made by Glidden. When I went to take the tape off for the striped wall not only did pieces of the red come off, but the primer came right up with it. I am left with a beautiful red wall with ugly flourescent green tears on it. It literally ripped up like paper. I waited 2 days between the primer being applied and the paint being applied, and the paint was allowed to dry for 2 days as well. Any idea why this happened? Is there any easy fix? I don't want to have to purchase more primer, sand paper etc and start all over again. Please help.