is possible if unprotected sex is done around ovulation time.
In your case, chance is there.You have to take emergency pill which are effective if taken within 72hrs of sexual intercourse.
But you never take Emergency Pill with other drugs used in IHD. As it decreases the efficacy of the pill.
So wait for the next coming period and if missed, do a urine test after 1wk. Check result and consult with doctor.
Be well and practice safe sex