I ejaculated inside my girlfriend maybe during or a week after her ovluation, took Plan B one step 2 hours after sex. What are the chances? Need tips

A big "tip" Clearly this episode of intercourse did not provide for a condom to cover the "big tip". Thus, Plan B was needed to abate the lack of "foresight" with the foreskin. Plan B doesn't always work but a condom often does.