Broken collarbone; Worried about return

2 weeks ago I broke my collarbone skateboarding. I was just getting really happy with my progression before I was injured. I'm worried that after the doctor says I am okay to train again I'll have digressed horribly. Every once and a while I go over flips and different moves in my head to try to retain some muscle memory but besides keeping my legs and such in shape I can't practice at all. So my question to you guys is, coming back from an injury was it hard to return to your previous skill level? Thanks.