I just want a doctor to listen to me!!!

For months & months now, I've been having EXCRUCIATING pain in my abdomen after sex. So bad that I'll go to the bathroom and shake, sweat, have a fever, & vomit. It usually goes away within 10-15 minutes but during that time I feel like I'm going to die. I went to a obgyn & she didn't listen to me at all. Completely disregarded it as normal. I am very in tune with my body, & this is not normal. I know something is wrong. I've been testing for a few things but nothing very in depth. I am posting this to ask if any one else has experienced something like this and if they ever got any answers. Im worried this could some day affect my ability to get pregnant. Thanks so much in advance