Pregnancy chances without insertion. But spotting observed on second day

Patient: I and my girlfriend got intimate, had foreplay but no penetration at all. All i did was rub my penis on her external genitals. No Ejaculation. We both are virgins and i had inserted my fingers in her vagina for the first time and she said it hurts and i did not continue She told me that she is missing her periods (even on the day of this foreplay) and she says she observed a spot of dried blood on the next day of the foreplay. She is scared that she is pregnant (on the second day of foreplay), What are the chances of her getting pregnant?

Symptoms: Spotting, missed periods