You are a known patient f IBS
disease and lactose intolerance
means you have been seen by Doctors and must have known the things to eat and not eat.
Since you have taken Wheat and dairy products in spite you knew of the complications indicates that the diarrhea
with changing consistency and color can be due to intolerance and additional intestinal infection as the stools are fouls smelling.
I would advise you the following in such a situation:
Send the stool for lab to see if there is any evidence of an intestinal infection.
Also get the blood tests as the raised white cell count can tell about the possible infection.
If the tests are positive for intestinal infection then a course of an antibiotic active against intestinal infection Ornidazole
and probiotics can help you.
Stop taking any foods and beverages that you know can instigate or enhance your problems.
Use boiled for 20 minutes and cooled water.
Take probiotics for a long time.
Curds/yogurt and bananas along with activated charcoal
can help further.
Consult your Doctor for clinical evaluation and correlation with the lab reports, get referred to a Gastroenterologist and further investigations with management as required.
Hope I have answered your query. Let me know if I can assist you further.
Dr. T Chandrakant,