Postpartum AF or Pregnant?

Julia • Mom of 3 boys

I probably just need to take a test. But since I can’t make it to the store just yet here’s my question. I’m 7 months postpartum and breastfeeding. I pump once or twice a day while at work. The last week my nipples have been so sore and I thought it was from breastfeeding but no cracks or anything and they even hurt when shower water hits them. Plus I’ve started to have mild cramping. Could this just be a sign of my first Af or could I be pregnant? Anyone have this before?