Since you seem to be offline, ill leave a response here which we can discuss later on.
From what you are describing there are two things which are concerning here. The first one is the presence of black bowel movements. This is known as melena, which is an indicator of bleeding in teh stomach, oesophagus or the first part of the intestine. This can be due to an ulcer, inflammation of the lining of the stomach. This is something which needs to be evaluated ASAP as bleeding if left unchecked could be catatstrophic. This would need to be evaluated with a stool for occult antigen and an endoscopy as well. If you are on iron or use peptobismol frequently then it can be a cause for the black colored stools.
Now the pain in teh regions which you have described can be due to electrolyte imbalances which can occur due to dehydration or even due to a long standing chronic medical condition. this would need to be evaluated with the help of tests for potassium, calcium and magnesium. Another cause of the pain can be due to autoimmune disorders which can also cause bleeding from the stomach etc as well as muscle pains as well as joint pains. This would be evaluated with the help of ESR and ANA and if needed a complete ENA profile.
Another cause of this could be related to a muscular disorder such as myositis or myopathy which can cause muscle tenderness as well as pains. Again blood tests like CPK and LDH would be useful here alongwith a EMG test as well.
There are other causes which can cause these symptoms which include chronic medical conditions such as liver issues as well as renal problems. That is why a complete blood chemistry profile should be done.
Now i would suggest that you have your doctor look into these posisbilities ASAP especially regarding the black colored stools.
Do you have any more questions?
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