thank you for your query.
your complaints point towards Lactose intolrenace teh symptoms of which include-
Pain or cramps in the lower belly.
Gurgling or rumbling sounds in the lower belly.
Loose stools or diarrhea
mucous in stools
what you are experiencing is the adult form of lactose intolreance due to lack of enzyme lactase.Symptoms of this often start during the teen or adult years and continue for life.these last as long as the small intestine
does not make lactase.
you can get specific tests done to confirm this.
till then i would advise conservative management consisting of
avoidance of dietary lactose, substitution to maintain nutrient intake, regulation of calcium intake
hope the information was helpful,
you can contact me for any follow up questions