For a month I have been experiencing poor concentration, appetite increase, fatigue, irritability,chronic hair loss, loss of menstrual cycle, and headaches. I got blood work done and my WBC was on the low side. I want to know if these symptoms and the low WBC are related. What could be causing these symptoms?

WRongdiagnosis.com gives four possibilities for hair loss, fatigue, and an appetite change.
Appetite changes and Hair loss and Tiredness - Multiple Symptom Checker - WrongDiagnosis.com

I'd guess low thyroid as the most likely of these, especially with the menstrual symptoms unless you have reason to think it's one of the other three.

Hyperthyroidism - Wikipedia, the free encyclopedia

Hypothyroidism is very treatable if that turns out to be what you have. Ask your doctor to check your thyroxin levels. But I don't think that would explain the low WBC. How low was it?

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