Question-arm popping?

I had a seizure about one week ago and like the rest of the seizures (grand mals) I don't remember anything about it. I do know that I must have fell on my left arm/shoulder because it was sore for the next few days and it had some scrapes and cuts on it. 

What is different about this time is that whenever I put my left arm in a certain position, it "pops."  The pop is loud enough that my girlfriend could actually hear it too.  It's not really painful, although it might sound that way, it's more just a weird feeling when it happens. 

My question is if anyone else has had this experience and if so, what is it?

PS - I know this might be more of a medical question (non-seizure related) but I thought I might ask it anyway and see if anyone has any solutions.