Having Noticed A Delay In Periods Due To A Cyst In The Ovary

Hi, I went for scan last week and I was told I have ovarian cyst and its not big. So I was placed on Ampiclox and Kotase tablet, what I noticed was I haven t seen my period which I was supposed to see on the 18th and today is 23rd what could be the problem. Secondly! Have had this Cyst sometime january which I was told to use Antibiotics and I did why am I having it again and what are the Risk of getting pregnant with cyst? Can I get pregnant or it won t allow me to get pregnant. Will it cost miscarriage? Thanks in anticipation