Pregnancy risk (broken condom)

Patient: I had protected sex with my girlfriend last night. Today we had sex again (no shower) and the condom came off before ejaculation. How high are the chances of pregnancy? She has twice previously used morning after pills and they had really adverse side effects on her. She is on day 20 since the start of her last period. What should we do? Are their other effective contraceptives you can recommend that don’t adversely effect her hormones?

Symptoms: Possible pregnancy