Birth control and sex

so me and my boyfriend have been dating for 2 months, and we are sexually active. Ever since we first started dating we used the pullout method - never used a condom. We had a few scares where he got a little bit inside and what not and we always took a test of we were scared. I took a test and it did come back negative and I haven't missed a period while dating him. I told my friend about this and she said she would give me her pill that has 2 months left on it - I am worried that because I haven't gone to the doctors I don't know what's going to happen to me. I understand what to do with the pill but I am just making sure that is not dangerous. I am 14, and have been taking it for 2 days, and I understand to use protection for the first 14 days. Is there anything I should or shouldn't be doing? help. Thankyou