Don't know if you're still having this issue, but I've only just read this message and wanted to tell you that after my first c-section, I was feeling them up to 2-3 months later, too.
I had a fairly traumatic EMCS and the scar is unusual, and I bled for nearly 8 weeks after. So that may have something to do with it. Then again, maybe not. But I did want you to know that I felt the same. I always just assumed it was my uterus getting back to normal. But then I felt them every month before my period for up to about 2 YEARS after the birth!!