1. Sounds like a case of haematochezia. If the amount of blood loss is severe enough, it can certainly cause weakness, light-headedness, low blood pressure and symptoms of anaemia. I'm surprised that her doctor is clueless. These symptoms are common among 15% of adults, and there are treatment protocols within the conventional medical field.
2. Please consider a visit to a classic homoepath. He/she can treat here general condition in a so called constitional treatment.
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