Found a wonderful book on serotonin, its functions in the body and how it relates to estrogen levels in women. Key: low estrogens - low serotonin. May be explaining why I felt so low and misserable in the past three months until I tested my estrogen levels and got on HRT.
"Secrets of Serotonin" by Carol Hart, Ph.D. - purchased it from Amazon on the Kindle. Still have not finished it but decided it is worth sharing here.
Also the book talks about antidepresants and how they function, also the research related to the doubtful effects of them on mood, etc.