late period, stopped birth control, have had clot like clear

I am 2 days late in getting my period. I had been having unprotected sex with the same partner for the past 3 months although haven't had sex for almost a month. About 2 weeks after my last period and last time with intercourse, I had a clear/cloudy discharge of a clot-like substance which was also stretchy. I have also recently stopped taking my birth control, ortho-tri cyclen after my last period. This discharge has only happened once but was wondering if it could be due to stopping birth control, unprotected sex, or possibly pregnancy. I also just travled from spending 4 months in Australia and have heard that travel can also affect your period. Thank you