How many calories are you eating and what are your ratios like? I think some people have a fat phobia and don’t replace the carbs they cut out with anything. Getting a poor balance is going to leave you chronically fatigued.
1) Get at least 55g of carbs per day to keep your glycogen stores topped up. This allows your brain to run on glucose, gives your muscles an energy source for sudden physical exertion, and takes strain off your liver and kidneys. It also reduces the chances of protein being burned, which creates ammonia as a by-product and wastes muscle. It’s a bit tricky on the diet, but there are carbs in there if you look.
2) Get most of your calories from fat. You’re already eating the carbs your brain needs if you follow #1, but cells containing mitochondria, like the muscles, run better on fat. Years of anti-cholesterol, low-fat brain washing may mean you’re starving them of energy. Check how many calories you’re consuming from fat.
3) Get the rest from protein. An excess causes the liver and kidney issues, and has been linked to lower life-span, so you don’t want to go crazy with protein. If you aren’t getting enough carbs to fuel your brain, you need over 120g/day depending on your weight, but anything from 50-150g or so should be okay if you are. You’ll be fine at the low-end unless you workout.
I never thought much about this ratio until recently, but it definitely makes a difference. You can see how the amount of carbs affects the amount of protein you need, so they’re all interdependent, and if you aren’t eating enough of the right stuff, it’s no surprise if you end up feeling drained. That said, since you’re only one month into the diet, your body is probably still adjusting to the dietary change.
If your shoulder injury is just pain, i.e. not a wound, it could be inflammation. Die-off contributes to inflammation, and so does diet, stress and (lack of or too much) exercise. Anything else keeping your body from running at its best – candida, deficiencies, immune issues etc – obviously isn’t going to help.