2 Days Ago I Developed Stomach Cramps And Could Only

2 days ago I developed stomach cramps and could only pass small amounts of yellow diarrhea ! Had to go multiple times a day and night to get minor relief the stool was mucous and smelled very different today I am still cramping and the stool is pink mucous and fishy smell 71 year old male and have had 3 colonoscopys to date. I had only a burger on the date it started. Felt fine for about 3 hours then it came on suddenly. I'm also having trouble urinating and have enlarged prostate with history of prostate infections. I started on cipro today that I have in reserve