Brief Answer:
Listed a few possibilities, pls also increase fluid intake for now

Detailed Answer:
Hello sir and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. With no other accompanying symptoms, the list of possibilities is vague and could be long, but I shall list the most likely causes for your reference sir:

+Hypoglycemia (drop in blood glucose levels): If you are a diabetic on medications or are on a strict diet, then this could be a possibility. If you are not diabetic and consumed a less amount of food earlier that night or indulged in strenuous exercise, or any other cause that could result in a drop in blood glucose levels this could be a possibility

+Temperature changes in the surroundings: This could also be a cause and only you would know if we can rule this out or not sir

+Stress/anxiety/depression: A high amount of stress or anxiety can also lead to both sleeplessness and increased sweating

+Urinary tract infections: Also cause excessive sweating and chills at night, but is also accompanied by increased frequency of urination

+Increased sweating, increased thirst, increased hunger, increase urination are all also associated with diabetes and this should indeed be ruled out

+Infections (e.g. viral infections, pneumonia, etc.)

+Thyroid abnormalities

+Side effect of medications
and a few other causes

But I do not think this is anything serious, but I would recommend an elaborate evaluation to check on your general health and also diagnose the cause for the night sweats and chills. Do not worry sir, and if at all it does recur then you should consider visiting your doctor.

As for the leg cramps and stiff neck, if these occurred simultaneously with he night sweats or the very next day then they are almost obviously due to dehydration. I would strongly recommend increasing your fluids intake (at least 3 litres per day) and if possible have drinks with high electrolyte content.

I hope you find my response both helpful and informative. Please feel free to write back to me for any further clarifications, I am always here to help.

Best wishes.

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