Scared about Everything

My boyfriend and I had unprotected intercourse and he pulled out after like five thrusts. I wasn't too worried at first, but now I am terrified so I told my mum. She doesn't know anything about plan b, or that you can buy it over the counter. Now I have a doctors appointment for 2pm. Do you think they will prescribe Emergency Contraception? They wouldn't tell my mother or I on the phone. I'm low key freaking out and feel like such a loser, and I know I'm probably going overboard with all this. I wish they made a manual for adulting.