High risk

I have a question. Please no rude comments. I had a premature birth almost 5 years ago. The doctor never told me if I was high risk and I was talking to a friend who also had a premature baby and told me I am high risk due to the fact that I had I had a premature baby. I am pregnant and I've been having sex and masturbating. I am scared I am harming my baby. I have an appt tomorrow and am gonna ask. I feel like a horrible mother... But I didn't know. Has anyone been through something similiar.?