If I couldn't get a loan for summer cles in college, how will I be able to get a loan for med school ?

Hi, I'm a Biology major at St. John's University (starting 3rd year in September) and I wasn't able to get a loan for $3000 for cles this past summer .. My fathers credit is shot, my mom is unemployed and a student herself, I have no income nor any worthy co-signers (I come from a not so fortunate background) .. So I was wondering how will I be able to pay for Med school ??