I'm scared and so nervous.

I was always told I couldn't get pregnant I have endo and my whole family basically has it and always had miscarriages and eptopic pregnancies. I went to the doctor today for severe stomach pains and found out I'm pregnant. Not sure how far I was too shocked to find out exactly, I go back next week. But there's no denying this test... my fiancé was with me when they told me and he was super excited at first but that quickly turned to terror and worry..... guys what if I suck? I'm not ready. I am so scared the pain means there's something wrong I have an ultrasound next week.... I'm so so so scared.