The causes of sudden dizziness and sweating lying down for a while will be fine are overwork, postural hypotension, mental illness, and ear-source diseases. 1. Overexertion: If you have recently been under too much pressure or suddenly suffered from mental stimulation, you may experience unstable nerve function, leading to dizziness attacks. 2. Postural hypotension: sudden change from squatting or lying position to standing position will result in short-term insufficient blood supply to the brain, causing dizziness and sweating, which will be relieved when the blood supply to the brain is restored after resuming the lying position. 3. Mental illness: depression, anxiety disorders and other neurological disorders, causing dizziness. In addition, panic attacks will appear for a short period of time serious autonomic dysfunction, bleeding dizziness, sweating. 4. Auricular diseases: dizziness, nausea, and false sweating caused by changes in body position will occur. If this happens often, you should consult a doctor in time to clarify the cause of the disease and then targeted treatment.