Hello! I have been through your question. Related your symptoms I think this is an intestinal infection and most possibly shigellosis. Usually diarrhea with mucus and red blood is strong suspicious for an intestinal infection caused from shigella. What I suggest for you is to do a physical examination by an Infectious diseases specialist,to tell him some more detailed epidemiological data (recent travel history and similar symptoms with family member) to do a differential diagnosis with crohn s diseases and ulcerative colitis , do full blood count, azotemia / creatinine and stool culture to define better the diagnosis and to start the treatment with bactrim or ciprofloxacin (if verify shigellosis and if you aren t allergic) for 5 days. I hope my answer help you. I wish you a quick recovery.