It might mean endo is on or even in the bowel, but less than 10% of endo ladies have bowel endo- and a whole lot more than that have digestive issues with endo.
More commonly the bowel, or the colon and perhaps some intestines too, get caught up in scarring and adhesions which can be triggered to grow by endo elsewhere, and they keep on growing till they stick to something else nearby and carry on growing.
They can really restrict tubes, vagina, cervix, fallopian tubes, bowel, colon, ureters etc.
Where endo can be rather patchy and grows on surfaces as rather a flat growth, adhesions can rapidly head in all 3D directions. Acting a bit like a corset round tube like structures.Sticking organs and ligaments and other tissue together, they can create what is called a frozen pelvis, where most things are stuck in the gluey mesh to everything else and this really does restrict their mobility and their ability function without causing pains.
Having endo is also known to cause a change inside the guts, making them very sensitive to irritatant foods and drinks. It is not necessarily endo that is growing there, though it can be that, but a change is caused in the body that makes endo ladies a lot more likely to get IBS along with having endo. The endo may only be a tiny patch somewhere quite remote from the digestive system, but still cause gut problems.
The following paragraph is snaffled from the centreforendo.com website
"Even when endometriosis does not occur directly on the bowel, it can cause bowel symptoms. Inflammatory mediators can affect the bowel and contribute to them. Inflammatory mediators are released by tissues in response to inflammation or injury, and include prostaglandins, tumor necrosis factor (TNF), interleukins and cytokines. They create changes within the tissues and can cause new blood vessel growth, attract other things to the area such as white blood cells or contribute to scarring. Prostaglandins, which are released from the endometriosis implants and uterus during menses, can cause smooth muscle contractility. This not only affects the uterus, but can also cause increased contractility of the bowel. In these cases, diarrhea and intestinal cramping can result."
In my case, when I do get excess gas, perhaps had a sip of cocacola or champagne at a wedding reception, or eaten a sprout or two..... then it's a matter of minutes and whoa the pain starts building up in the region of my colon. The pain is right across my tummy just above where the uterus is. Not higher up or lower down in the bowel, but right about colon level and even if I do manage to get to the loo or pop outside to let out the gas, it still seems to take quite some time for the pain to ease off, even though there isn't any gas pressure still there.
My best advice for you is to work out for yourself and your body, which are the foods and drinks that seem to bring on wind pain and avoid scoffing those and stick to what I call the safe foods for you. We all are different to some extent about what foods and drinks will have the worst impact on each of us, it is trial and error over the coming months, noting down what you have eaten and drunk before pains hit you. Keeping a pain diary may help to identify the culprit foods and drinks.