Could this mean preterm labor?

Im 26+3 weeks today and for the past few nights I've been having what feel like strong menstrual cramps. I know they arent BH because i also get BH and it feels completely different. Sometimes it in my pelvic area but its mainly on the inside of my body (i really dont know how to explain it) its accompanied by very uncomfortable pressure when it happens as well. It doesn't occur in any pattern it cant be timed. But its very strange. From what I've researched it doesnt seem to be Round Ligament pain either. Ive been to the hospital multiple times for leaking but the amniotic fluid test was always negative. Im not going back to the hospital because I'm sure i look crazy by now lol I was thinking about checking my cervix while in the shower to know if im dilating. With my first pregnancy my water broke at 39+2 and i wasnt dilated until my water broke randomly. Could the cramping and pressure be a sign of preterm labor? Or is this normal?