Does pumping cause cramps?

I know that immediately postpartum pumping breastmilk and nursing causes uterine cramping (ie, "after pains"). My daughter is 3½ months old now. I experienced those normal cramps in the first week or two after my baby's birth but they stopped. Until recently... All of a sudden I'm having weird cramps and they're worse when I'm pumping milk.

Is this normal? Has anyone else experienced it this far off from delivery? What the heck do you think might be going on here?? I did restart my period this past month. There's no way I'm PMSing or about to start because I'm less than a week into my cycle.