What Are The Chances Of Pregnancy Despite Taking Plan-B While On Junel Fe?

Hello, I am on birth control (Junel fe-the combination pill) and have been in it for about a year and a half. I take it around the same time everyday (plus or minus 2 hours). I had my placebo week Sunday june 25- Saturday July 1st and the next day, Sunday July 2nd, I started my new pack of pills. The day after, July 3rd, my boyfriend and I had sex with the only contraception being my birth control and the withdrawal method. During sex, we were switching positions (his penis was not in me at this time) and a whitish/clear fluid came out of his penis. We re thinking it was his precum because he did not orgasm when this happened. We contined having sex after that and he finally came (but not in me). A day later I was paranoid by the fact that we continued having sex after the whitish/clear fluid (precum), so I took a plan B about 40 hours later. I am having some symptoms from the plan b such as white vaginal discharge and cramping but that s it. What is my chance of pregnancy?