Continuing the off topic theme.
There are a few sunken huts on the edge of the river near Baimachang, after the recent earthquake the land sunk. The huts were in about 2m of water. With the rains they probably disapeared.

Imagine if this happened 200 years ago, or more. Before photograhs, with local enbelishment generation after generation. The huts become a village, then a town, then a city. The river then could not swallow a city, and so it morphs to a local lake (if there is a local deep one). Fishermen of old used to drag up artifacts, but not for a hundred years or so.

Staying well hydrated, easy to neglect this if you don't want to pee in public restrooms. Otherwise it is harder to assimilate nutrients in all the other goodies we consume.
Potassium from well ripened bananas.
Don't forget calcium, helps protect from cramps too.
Red fruits.

To feel like a 'squib'?

Ginseng tea. Sometimes I felt wired but I had to stop as it gave me palpitations, and a cracking hangover about 2 hours after drinking it. You may be ok.

Problem with most stims like caffeine is that they give you a boost by using reserves from the liver. This is not repeatable in rapid succession, and actually there is a come down from having no reserves.
Redbull with caffeine and taurine fine just before strenuous exercise. Most energy drinks are just high sugar. Unless you exercise they are 'liquid fat'.

The other thing I would suggest, is that getting depressed, or suffering with anxiety, are normal reactions to the big C. If you are a foreigner and you don't get depressed/etc., you are either very lucky, exceptionally resilient, or on something.