I copied this from an answer in Yahoo Answers:
Colorectal polyps
A colorectal polyp is a growth that projects (usually on a stalk) from the lining of the colon or rectum.Symptoms:
Constipation
Dark colored stool
Black stools
Change in bowel habit
Blood in stool
Crohn's disease
Crohn's disease is a chronic autoimmune disease that can affect any part of the gastrointestinal tract but mo...Symptoms:
Fecal incontinence
Feels hot to touch
Aversion to food or drink
Weight loss
Blood in stool
Colon cancer
Colon cancer is cancer that starts in the large instestine (colon) or the rectum (end of the colon). Such can...Symptoms:
Nausea
Rectal bleeding
Unintentional weight loss
Pale skin
Blood in stool
Peptic ulcer
A peptic ulcer is erosion in the lining of the stomach or duodenum (the first part of the small intestine). T...Symptoms:
Chest pain
Weakness
Vomiting blood
Tired
Blood in stool
Colitis
Colitis is an inflammation of the large intestine (colon).Symptoms:
Dehydration
Night sweats
Aversion to food or drink
Crampy rectal pain
Blood in stool
Necrotizing enterocolitis
Necrotizing enterocolitis is an acquired disease, primarily in premature infants or sick newborns, in which I...
This condition is considered a medical emergency. Urgent care may be required.Symptoms:
Dark colored stool
Black stools
Nausea
Feeding difficulties
Blood in stool
Ulcerative colitis
Ulcerative colitis is a chronic , episodic, inflammatory disease of the large intestine and rectum characteri...Symptoms:
Feels hot to touch
Pale skin
Fever
Crampy rectal pain
Blood in stool
Bleeding
This condition involves losing blood. This can occur internally (when blood leaks from blood vessels inside t...
This condition is considered a medical emergency. Urgent care may be required.Symptoms:
Shock
Fast heart rate
Blood pressure - low
Pain
Blood in stool
Thrombocytopenia
Thrombocytopenia is any disorder in which there are not enough platelets. Platelets are cells in the blood th...Symptoms:
Bruises
Heavy menstrual period
Bleeding gums
Bleeding
Blood in stool
Hemophilia A
Hemophilia A is a hereditary bleeding disorder caused by a lack of the blood clotting factor VIII. Symptoms:
Shortness of breath on exertion
Joint pain
Tired
Pain
Blood in stool
Colorectal polyps
A colorectal polyp is a growth that projects (usually on a stalk) from the lining of the colon or rectum.Symptoms:
Constipation
Dark colored stool
Black stools
Change in bowel habit
Blood in stool
Crohn's disease
Crohn's disease is a chronic autoimmune disease that can affect any part of the gastrointestinal tract but mo...Symptoms:
Fecal incontinence
Feels hot to touch
Aversion to food or drink
Weight loss
Blood in stool
Colon cancer
Colon cancer is cancer that starts in the large instestine (colon) or the rectum (end of the colon). Such can...Symptoms:
Nausea
Rectal bleeding
Unintentional weight loss
Pale skin
Blood in stool
Peptic ulcer
A peptic ulcer is erosion in the lining of the stomach or duodenum (the first part of the small intestine). T...Symptoms:
Chest pain
Weakness
Vomiting blood
Tired
Blood in stool
Colitis
Colitis is an inflammation of the large intestine (colon).Symptoms:
Dehydration
Night sweats
Aversion to food or drink
Crampy rectal pain
Blood in stool
Necrotizing enterocolitis
Necrotizing enterocolitis is an acquired disease, primarily in premature infants or sick newborns, in which I...
This condition is considered a medical emergency. Urgent care may be required.Symptoms:
Dark colored stool
Black stools
Nausea
Feeding difficulties
Blood in stool
Ulcerative colitis
Ulcerative colitis is a chronic , episodic, inflammatory disease of the large intestine and rectum characteri...Symptoms:
Feels hot to touch
Pale skin
Fever
Crampy rectal pain
Blood in stool
Bleeding
This condition involves losing blood. This can occur internally (when blood leaks from blood vessels inside t...
This condition is considered a medical emergency. Urgent care may be required.Symptoms:
Shock
Fast heart rate
Blood pressure - low
Pain
Blood in stool
Thrombocytopenia
Thrombocytopenia is any disorder in which there are not enough platelets. Platelets are cells in the blood th...Symptoms:
Bruises
Heavy menstrual period
Bleeding gums
Bleeding
Blood in stool
Hemophilia A
Hemophilia A is a hereditary bleeding disorder caused by a lack of the blood clotting factor VIII. Symptoms:
Shortness of breath on exertion
Joint pain
Tired
Pain
Blood in stool
Source(s):
That is some I know of. I think you should consult a doctor
