Brief Answer:
It can be due to many other causes exept bleeding.

Detailed Answer:
Hello!
I am Dr.Rovena
I had gone through your query and understand your concern.
Anemia is a medical condition in which the red blood cell count or hemoglobin is less than normal.
Anemia is caused essentially through two basic pathways:
-a decrease in production of red blood cells or hemoglobin, or
-an increase in loss or destruction of red blood cells.

Some of the most common causes of anemia include:
-Vitamin B12 deficiency may cause pernicious anemia.
- iron deficiency is a very common cause of anemia.
-There can be rupture or destruction of red blood cells (hemolytic anemia) due to antibodies clinging to the surface of the red cells.
-A wide assortment of bone marrow diseases can cause anemia.
For example, cancers that spread (metastasize) to the bone marrow, or cancers of the bone marrow (such as leukemia or multiple myeloma) can cause the bone marrow to inadequately produce red blood cells, resulting in anemia.
-Acute blood loss from internal bleeding (as from a bleeding ulcer) or external bleeding (as from trauma) can produce anemia in an amazingly short span of time.


I wrote you all this to make you understand that are too many causes of severe anemia.External or internal bleeding is only one of the causes.
I need you to write your medical history:-When have you been diagnosed for the first time with anemia?
-Do you suffer from any other disease?
-Please write to me all your symtoms(everything you think isn't normal for you body)

In order to give you my opinion related to the cause of your Anemia I need you to upload all your test results,everything you have done until now.

I will be waiting for your answer.
Regards.
Dr.Rovena

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