Horrible Cramping

I just got my 21 week mark today, as I got ready for bed I started having the worst cramping I’ve ever felt in my life. It’s mostly constant, the pain hasn’t yet gone away. It’s so bad it’s making the whole left side of my body hurt as well. I haven’t noticed any bleeding vaginaly which I’ve been checking frequently since this has started. Asl this is about the time baby starts to kick a lot, I haven’t felt her kick once. Should I be worried or is it just my body just changing to make room for baby?