You should see a doctor. There are a number of things that can cause night sweats and fatigue. But one is heart problems. My mother has the same problems. Early stages of heart disease cause fatigue and sweating. This might not be the problem, But it needs to be ruled out.
There could be a lot of different reason, if you are female and middle aged, it could be menopause, but it can be a sign of a minor infection to a serious illness, see your doctor as soon as possible.
In women, night sweats and fatigue may be caused by hormones. In anyone, chronic fatigue syndrome could be present, which can be diagnosed and treated by your doctor.
