Hello, my friend, according to your description, considering your present situation, it is a phenomenon of transitional fatigue, a sudden change in the law of life, an adaptation to jet lag, and a certain amount of physical exertion.

Guiding opinions:

According to your current situation, I suggest you adapt to this environment and work as soon as possible, and pay attention to rest and sleep time. Secondly, pay attention to eating high-protein food, lean meat, milk and eggs, which will gradually improve. I hope my reply can help you!