What Are The Possibilities Of My Girlfriend Getting Pregnant?

SO my girlfriend and I were having some fun one night and we ended up grinding each other without having sex but my penis was touching her vagina. I couldn t remember if i had ejaculated or not when doing this because I didn t feel an orgasm but she was worried that I did. Even if I did ejaculate it would have been on the outside of her vagina. Is there still a possibility of her getting pregnant? Also her mom gave her these pills to take because she is going to mexico when her period is suppose to come. Im not sure what the pills are but she said they are some type of birth control? will this effect her and the possibility of getting pregnant?