On off cramps

Annette • Just got my bfp with our rainbow baby 🌈
I'm 29 weeks + 2 days and I have cramps very very low down they come in waves, I know it's not contractions they don't tighten and the waves literally last 2 seconds. Feels very sharp and painful. I guess it's just baby moving and getting heavier but I just wondered if anyone else feels this?