Dr. Dan

6 mg of Lunesta? That's a hefty dose.

- Dan

Lunesta appears to be metabolized by the liver. All that water drinking is likely not necessary or useful.
It also appears that the liver enzymes used to break it down are influenced by several other drugs and some foods. Similar to the problems with certain drugs and grapefruit that you may have heard of. You might look over that list to ensure you don't have a confound.
The best treatment for PTSD, anxiety or panic attack is likely cognitive behavioral therapy. Benzos and or SSRI anti-depressants would bring relief quicker but with many sides and they are a real slippery slope. Withdrawal for either is a bitch.
A less stressful occupation might be something to consider. Few of us however have the option of picking our job. We take what we can get many times.