Welcome to HCM,
You are having basically 2 medical issues first one is GIT blood loss and Gall stone.
Usually GIT blood loss result in Iron deficiency anemia
, this blood can come from upper portion of GIT that is stomach, Duodenum where Acid peptic disease
and ulcers are common cause,other common cause is use of alcohol which can cause bleeding from stomach or also as complication to liver disease, esophageal varices
Other cause may be malignancy,adenoma,polyp etc.
If fresh blood is passed then source could be lower GIT colon or rectum,even piles.
You must see Physician/Gastroenterologist and after CBC,Peripheral smear study,other liver function ,Lipid Profile
and kidney function along with Upper GI endoscopy or colonoscopy as required may be performed to know the source of bleeding.
One very important cause could be analgesic use like aspirin/Diclofenac like NSAID.
You should stop alcohol or tobacco if you take.
You are not having symptoms of gall stones they are mostly made from cholesterol
so Statin or Oral bile acid therapy could help(UDCA)
Please take care