Weird feeling left breast

ShrugBug

I’ve having this very weird feeling in my left breast only. It’s like a small wave of pain. Not really sore per se but not unbearable. I had sore breasts with my first pregnancy but this is completely different plus my period is due in 10 days. It almost feels like it’s in the very back on my breast or inside if that makes sense but I feel ntn to touch.