How To Differentiate Between Periods And Bleeding Due To Breaking Of Ovarian Cyst?

hi i have been living in turkey and i went to the hospital as i had a cyst in my ovavy which was 3cm the doctor gave me tablets which would break down the cyst i went back 2 weeks later to see the cyst had reduced to 1cm however me and my husband had been trying for a baby i informed the doctor and she said you should continue to try in the next three days as i was most fertile so we did now im back in england and i thought i was pregnant however i came on my period yesterday could it be possible i am preganant and the cyst is breaking up just need advice please