Need Some Advice

 So last night i had sex with my boyfriend with a condom on and when he pulled out it was broken i went to the bathroom and immediately started crying. Im 15 and im terrified. I told my sister about what happened and she said its not a guarantee that ill become pregnant. Im just so scared and I dont know what to do. I dont want to become pregnant because 1: im not ready and im still in high school. 2: i feel like my parents wouldnt love me anymore. 3: i wouldnt be allowed to see my boyfriend anymore and I cant even imagine being happy without him because hes my bestfriend. Please give me some advice