Painful sex

I had my last child 4.5 years ago and ever since he was born i have been having a non stop problem with pain during sex as well during defecation. I had a surgery to check for endometriosis because i have nearly single symptom that comes along with it, but i do not have it. It hurts in the pelvic area/lower abdomen specifically. Drs cant tell me what is causing it. Also if i lay on my stomach and prop my head up on my hands or bend over from a standing position i will get dizzy and feel like the nerve where my epidural was placed is piniching giving me a instant headache along with nausea. I did not have these problems till after he was born. Has anyone else experienced this? Or any insight that could help?