Hi there, It is excellent that you ar seeking medical help.  It may be a number of things! If you couldn't or didn't  breastfeed, or even if you are ! It could be mastitis which is very painful and often needs antibiotics to resolve it! Blocked ducts  can pop up at any given time and cause all sorts of pain and infection. If you are breastfeeding, continue to try and feed from both breasts.If you are not breastfeeding, try and express from your breasts under a warm shower. Once you have a diagnosis it is easier to give advice! It may be quite hormonal, but if you have given birth in the last 6 months, it may be that your breasts arre still producing milk and if not expressed may cause pain and or infection. Good luck!

It may be hormonal or in my case it was milk.

When milk is not expressed properly either through breast feeding or mnaual/mechanical expression this may happen. When I started working again and stooped feeding my 5 month old, it happened, it will go away as soon as I am home and have fed him.

Don't worry, it may be nothing serious.

Best of luck!!!