Unsure of what is the cause

[Becsmum11]

Im a 40 year old woman and for numerous years have suffered from severe diarrhea and gas with odd pain sometimes in and around my whole stomach area. In the last year i have had a few episodes of constipation and have found that when i do any food that has been eaten that day causes me to be sick and the food is undigested and is very hard to bring up as its all merged together with no liquid to help it. This only happens when im constipated, as soon as im back to having diarrhea it doesnt happen although i do have nausea on most occasions. Has anyone else had this and had a diagnosis as to the cause