I get pains in my lower stomach and have been off and on for a few years no doctor can figure out what is wrong and I want help! I get these pains in my lower stomach and it feel like they run into my anus. I have had these problems at least 2 to 4 times a years since I was a teen, sometimes with sex and sometimes out of the blue. It hurt to make a bowel movement even though I force myself to and I can't get them to stop. The most relief I can get is partial with ib profen and hot baths but it doesn't get rid of the pain completely. It feel worse when I try to have a bowel movement or sit or walk or stand up. I have trouble sleeping when this happens. What is wrong with me!!

Gender and age? And by 'lower stomach' do you mean lower abdomen? Where EXACTLY?
How many doctors have you gone to, and what kind?

If I had to guess, I would guess a nerve is being irritated/pinched. I have a cluster of nerves that have bothered me for over 35 years, hitting my left abdomen, bladder, pubis, and bowel, and sometimes down my leg. No doctor was any help, not even a neurologist. A good chiropractor diagnosed it correctly, even though none of the pain is in my back, but the origin of the sacral nerves is the sacro-iliac bone in the back. I have scarring there. Not much can be done. Two treatments a week for months helped a lot with the far away pain, but whenever I do something strenuous, a lot of the closer pain comes back.

The trouble with nerve pain isn't just figuring out which of countless nerves is involved. It's also treating it, which can be very difficult.

Ibuprofin is for inflammation; Tylenol for pain. I take both, one of each, at a time, but I have inflammation from arthritis too. You should be taking more Tylenol unless you have a medical reason not to.