So this only started three weeks ago?
It could be IBS, but only a doctor can make the diagnoses. If this has only been going on three weeks, it make take a while longer to figure that all out.
In regards to IBS
"Also, air may accumulate behind these localized contractions, causing the bowel to swell. So bloating and abdominal distress may occur. "
"Some patients see gobs of mucous in the stool and become concerned. Mucous is a normal secretion of the bowel, although most of the time it cannot be seen. IBS patients sometimes produce large amounts of mucous, but this is not a serious problem. "
I would ask your doctor about the immodium. Its pretty safe, but you also want to know whats going on as much as possible.
let us know how your doing.