To me, lactose intolerance feels quite a bit like a gluten sensitivity when it comes to my gut - bloating, pain, constipation or diarrhea are often the result of consuming milk for me. About 50% of celiacs are lactose intolerant when they are diagnosed. After many months, or even years, many of those regain the ability to consume milk after their intestinal villi (which makes the lactase that digests the milk sugar, lactose). Healing can take a while, for me it took almost two years before I could have some ice cream without pain, and I still can not have it frequently or I feel a bit poorly - dairy less than once a week is all I can handle.
Many cheese's are lactose free. Lactose is a sugar and the hard cheeses have very little milk sugar in them. If you do have cheese, buy lactose free cheese or the very hard cheeses like cheddars.
Try going through all of your prepackaged foods, meds, and lotions/soaps. Maybe gluten is slipping through? Otherwise, I would cut out all dairy for a while and hopefully that will do it for you.
Hope you feel better soon.