I am not hard during the intercourse, but I am scared of the precum

hello everyone.... i have this problem well i dont even know how to explain it well but yeah.... im a guy who actually like to masturbate.. like almost everyday.. last week i have my first sex with my girlfriend and....during the intercourse, i feel weak, i dont even know how to do the sex position( well i know but i fail).. so yeah during that time, my girlfriend did tell me that my penis weak... i have to admit during the intercourse, i try to make myself please but in the end i fail, i didnt ejaculate i guess, but is there any chance that i precum, and yeah during the session, my lower and side abs hurt a lot when shes on top of me... i try my best i enter more than i could still ... i feel so weak.... so guys help me on this one.... any chance she might get pregnant? we didnt use any safety... we did almost an hour but i didnt feel that im ejaculating, plus my girl is so wet.... so any chance she might get pregnant??? please help me guys . thank you i appreciate your view