I think it could be connected.I know when I had my worst symptoms of PTSD, I had a compulsion to do things like check that windows and doors were locked, and check every room and under every bed when I came into the house or before I went to sleep. I literally could not stop myself. I checked that the door was locked so many times I loosened the screws and the doorknob started to fall off. I would get up in the night and check. Like...20 or 30 times. Now I don't do that, I manage to only check once, and resist any urges to get up and check again. So possibly?

If you think you have OCD related to PTSD I would talk to your therapist about it and see if you can work through it to get to a point where it isn't overwhelming. Hopefully that helps. :)