Brief Answer:
Proctoscopic examination of rectal canal should be done initially.

Detailed Answer:
Hi there,
Thanks for choosing this forum for your query.
Small amount of blood in stools can be due to a number of causes. However a stool test for occult blood should be done initially to make it clear if its blood or not.
There are numbe of conditions ranging from harmless illness to life-threatening disease which can present with blood in stools. Usually the blood will be bright red if the bleeding is from rectal or anal are(lower gastro intestinal tract) or if it flows freely and rapidly from the small intestine; if the blood remains in the gut for a longer time without getting passed in stools then the bacteria break down the blood cells and cause the black color so is the reason the stools are black in color sometimes.
You have not told the color of blood so if its bright red consider that site of bleeding is in lower gastro intestinal tract while in case if blood is tarry the site can possibly be in upper g.i tract.

Common Causes of bleed are-

Smoking, Regular alcohol intake,
Eating of spicy food and oily food.
Stress, strenuous exercise can sometimes cause.
Intake of any medicines or Drugs.


Anal Lesions:)(Bright red blood)
Inflammatory bowel disease
Fissure in ano
hemorrhoids
Rectal injury

So they are the most common causes. As you have not mentioned any history of yours kindly go through common causes first. If that's not your case then investigation of the anal canal should be done by proctoscope to rule out fissure, Hemorrhoid etc. an ultrasound abdomen should be done initially to rule out chances of inflammatory bowel disease.

Do you strain a lot while passing stools?
Are you constipated? Or do you ever feel constipated while passing stools?
Please let me know about your diet schedule too.

Regards.

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