I'm 22 weeks and I get the cramping to. Sometimes it feels like it doesn't release but if you feel that spot as it starts you can feel it tighten and release but the pressure feeling doesn't leave until I stretch it out. Could be what your experiencing.
Im 34 weeks & still get them. As long as youre not in a lot pain or bleeding its ok.
I'm 27 weeks as well but no cramps many women however do experience cramps on and off throughout their pregnancy I would say if u are not in extreme pain then it should be normal but if it increases or u start to bleed just head to the doc