I was wondering if there was a good chance if I could be pregnant. I was seeing a guy for a while, but the last time we had sex was on the last pill of my pack of last month (February 26). I had pneumonia for 3 weeks and finally went to the doctor to get antibiotics about a week after we had sex and was taking a pill for 5 days. However, a week before the placebo pill this month I experienced spotting for a day. And I was supposed to get my period Tuesday but it never came. Could this be due to the medicine I have been on.