Need advice after potential rape

!!Mention of potential rape!! I went through a situation and those I confided in told me the situation was rape. I am only 18. I live with my single mother who I know would understand, but I never want to tell her. I have Endometriosis. I also struggle with a lot of mental issues. The event only happened a week ago. My paranoia keeps suggesting I could be pregnant not know. I'm so scared. I have no money or way to get a pregnancy test to even find out. I do know he wore a condom. I stopped taking my birth control about a month ago. What can I do? Are there any resources to get that kind of test? I just don't wanna be pregnant. I want to finish highschool and be happy and move on. I want to forget it. My friends have all been commenting that I look different, a couple saying I lost my "sparkle", and they don't even know of the situation. I don't feel like me. My stomach has constantly hurt for a week and I feel horrible. I wanted to wait until marriage. Can someone give any advice?