hello and thank you for asking HCM,
I understand your concern especially while it is affecting your daily life. Symptoms worsen during your period because then you lose additional blood and as I understood you have iron defficiency. All these together make the symptoms worse. Black stool
appears while bleeding in the upper gastrointestinal system, for example in the stomach. You mentioned that you consume alcohol. Maybe you developed peptic ulcer
which is bleeding. Stool can be black while taking iron supplements
, but not while having iron defficiency.
My suggestion is to visit your doctor as soon as possible to make proper examination because with your now present symptoms and black stool you need urgent treatment and medication because your symptoms will become much worse.
I hope you will listen my advice and visit your doctor as soon a spossible.