What Could Sore Pimples On Areola While On Folic Acid Pills Suggest?

Hi, For the last week my breasts have been sore and the pimples on my areola are raised, red and sore and feel like they are on fire. I am not pregnant as I have started my period today. I have started taking folic acid to try and conceive and am on no other medication. I have never experienced this before during my mentral cycle.
zoe