I think I have sleep anxiety, or insomnia. At least every other week, I have a night where I have to take my melatonin pill. This week, I woke up in the middle of the night Sunday, slept well Monday, and had to take a melatonin Tuesday and last night. Every time I have trouble sleeping, I worry about it all day, worrying that I'll never sleep well again, that the melatonin will stop working, ...