Is Melatonin bad....

Melatonin is normally produced by the body at night. It's production is suppressed by light. 'Hormone' is just a type of protein in the body, not just estrogen but also testosterone, ACTH, CSH, etc etc.
It's called a 'dietary supplement' because it's not a 'drug'. Some technical FDA thing. The problem with supplements is that they're not regulated; studies have actually found real actual synthetic drugs in supplements, so make sure you get a trusted brand. When I couldn't sleep my clinician recommended melatonin, and she recommended Nature Made brand. Apparently they're reputable.
Melatonin seems to have fewer side effects from diphenhydramine HCl, and that makes sense since it's a hormone that your body is adapted to handle (drugs often have side effects because they react with more than one receptor in the body).

It takes about a week for melatonin to work, so give it at least that before quitting unless you experience side effects.

Thanks
Maria Carillet

Melatonin appears to cause very few side-effects in the short term, up to three months, when healthy people take it at low doses. A systematic review[63]in 2006 looked specifically at efficacy and safety in two categories of melatonin usage: first, for sleep disturbances that are secondary to other diagnoses and, second, for sleep disorders such as jet lag and shift work that accompany sleep restriction.[63]

The study concluded that There is no evidence that melatonin is effective in treating secondary sleep disorders or sleep disorders accompanying sleep restriction, such as jet lag and shiftwork disorder. There is evidence that melatonin is safe with short term use.[63]

A similar analysis[64] by the same team a year earlier on the efficacy and safety of exogenous melatonin in the management of primary sleep disorders found that: There is evidence to suggest that melatonin is safe with short-term use (3 months or less).