Breast pain

I have a weird pain on both breasts. On the left breast it is worse, it is on the left side (near my arm) and on the left underside. On my right, it hurts on the right underside and not nearly as bad. On my left side it hurts to the touch, and my right only if I press a decent amount of pressure. My period is supposed to be coming in 4 days and my breasts normally do hurt, just not to this extent and definitely not just from my arm touching my breast. I have 38DDD-38-Gs and I have never experienced this before. Does anyone know what this could be?