My boyfriend finished inside me on saturday 3/11 and i took a plan b pill 40 hours later. i am supposed to be ovulating tomorrow. is there any chance i could be pregnant? my last period started march 2 and i usually have a 30 day cycle?

Emergency contraception pills reduce the risk of pregnancy by approximately 75%. In other words, out of 100 women who have unprotected intercourse mid-cycle, approximately 8 would become pregnant. With use of emergency contraception pills, only 2 of the 100 would become pregnant, so there is a slight chance. ref: https://yalehealth.yale.edu/more/emergency-contraception-morning-after-pill#