Abdominal Pain, Vomit, Stools Dark, Smelly, Blood In Urine, Eat Healthy. Cause?

this is the third time in four days that i get a very bad lower stomach ache when needing to have a poo, it get so bad that it makes me vomit , but i cant go very easily to relive the need to poo, once i do start to go its in small amounts and i have to keep going back to the toilet every few minutes, its very dark and smelly, and i have noticed my pee has a small amount of blood in making it a bit pink, i eat very healthily , just raw salads a small jacket potato and fish or chicken, that is my normal diet