Stomach pains in pregnancy 17+4

With my 3rd baby, towards the end of pregnancy I would get these dull aching stomach pains that felt like I was up all night doing sit ups...especially in the morning after getting out of bed or if I got up during the night. It felt tender and sore even to the touch. I just figured it was my uterus getting stretched to it limits and the baby putting weight on it in my sleep? Well we had a surprise pregnancy and #4 is 7 months behind #3 at 17 weeks and 4 days and I am already experiencing these pains/pressure. I don’t know if it’s because I’m having them so close together or what. I told my doctor at my last apt that I’d been having some cramping and he said it’s not necessarily “normal” but that it isn’t “abnormal” either and to just take it easy and give my pelvic rest. Has anyone else experienced this that can possibly shed some light and calm my nerves lol thanks ladies