Hello Good Evening,
This is serious illness as per your description, although hemorrhoids can cause heavy and chronic bleeding
but any other bleeding source also can be found as you noticed dark red and thick blood also.
So you have to go to a surgeon for hemorrhoids diagnosis by Per Rectal and Proctoscopy examination to stop the further loss of any bleeding, moreover should be gone over a diagnostic Colonoscopy
to search a any other active source of bleeding.
This chronic and heavy bleeding can cause severe anemia
, which itself can cause severe weakness and many other serious symptoms.
So please do not take it lightly, go for proper evaluation and treatment (Blood transfusion
may be needed) and surgery may be needed.
Dr. Naresh Jain