Hallow dear, You need not be under such a stress. If you have solitary unprotected sex on fourth day of the menses, the chances of you becoming pregnant due to that act are practically nil. The egg release takes place 14 days prior to the next expected menses; i.e. if your period is of 30 days, your egg will be released on 16th day of the cycle. Hence I do not feel you should think of options for terminating the pregnancy. Probably your menses are delayed due to stress of unwanted pregnancy Wait expectantly for your menses to come. If they do not appear for one week more, then get your urine pregnancy test and/or ultrasonography done for detection of pregnancy. These tests done earlier are not conclusive. If by miracle you happen to be pregnant, then there are medicines Mifepristone and Misoprostol which can terminate the pregnancy. These are scheduled drugs, not to be taken OTC and should necessarily be taken by Obstetrician s prescription and under observation. I am sure this will bring down your stress. Please do not take any action in panic. Wait & watch.