6dpo pain under Lhs boob!

I’ve woken up this morning with this intense stitch like pain under my left boob.

It’s like ive been wearing my underwire bra all night but yesterday I wore a boob tube and freed my nipples cause they’re sore as fuck.

Also had intense lower back and front cramps last night that lasted roughly 5mins then went on and off then it was just a dull ache.

Just wondering wtf with pain is under my boob as it’s super uncomfortable!