Heavyness, pain puss in pimple on aerola

Today morning suddenly I felt pain on the left hand side breast when I checked it had one small pimple filled with pus under nipple on aerola. It pained the entire day and by evening little swelling and redness outside the Aerola increased.the pimple got burst however the pain is still there. Why it happened? I am 32 years of age and married from last 5 years I have no baby though I am trying from last five -six months to get pregnant but could not. My body responds after sex like little cramps, breast sensitivity, however till my period come sooner or later I get down. I feel my body might not be ready. This time I had heavy pain in the same breast. Hope both things are not inter related.pls suggest as I was thinking of getting breast cancer check