Am I over-analyzing this situation?

[layla]

I probably am severely over-analyzing, but I just wanted to make sure.

Alright, so my ex-boyfriend and I dated for a long time, I think it was about 14 months. Anyway, one year ago we ended things and it was incredibly hard for me, but I'm over him now (thank God, haha)
We have a lot of the same friends, and so even though I don't have him on Facebook anymore, I can usually still see a lot of his posts, because he'll post on my friend's walls. We even occasionally still see each other ina group setting, and text sometimes just to catch up.

So anyway, I've noticed that the last few times I've commented on certain mutual friend's pictures on facebook, he will comment right after. Like, seconds after. Usually, these are people he doesn't talk to on facebook. Am I just over-analyzing that he's doing this? I mean, it's probably just a coincidence right? And even if he was, what would that mean?

By the way, we're both in our early 20's.
Someone mentioned that I am "not over him". Oh trust me, I am. I am just CURIOUS. This is out of curiosity, not because I care about him in that way anymore. Geeze, people.