HI I am on glucophage for the last three months for PCOS . since taking it my cycle has been 28 days on the dot. my last period started on December 1st 2012 and was due December 28th 2012. however i am one week late. My husband and i had unprotected sex on the 7th and 13th of December, so i thought i might be pregnant. i have taken multiple home pregnancy test , all of which are negative. my breasts are heavy and sore, i feel slightly naseous, am very bloated and i have a white discharge which is not normal for me. i also have lower back pain and headaches. i realsie these are PMS or pregnancy symptoms , however, i do not feel any cramping to indicate my period is about to arrive. Please could you let me know what to do from here. thank you so much!