I believe that depends on the individual person. I sweat a lot while I am sleeping also and I have never been to Nepal. Try taking as cold as shower as you can stand before you go to bed and then sleep with nothing on and only a sheet to cover you to see if that helps.
Hi Kero! I hate that you got sick during your trip. I hope you still got to enjoy yourself - that is, if your trip was for fun!
As for the night sweats, it sounds fairly normal to me - especially since your immune system tends to lower somewhat when traveling long distances like Nepal. I tend to sweat a lot at night, sick or not. I bought myself a Chillo. I'm not sure if you're familiar with the Chillow or not, but it's a pillow that has cooling crystals in it and stays cold pretty much the whole night. You can stick it under your pillowcase or lay your head directly on it. I'm a HUGE fan of mine. Speaking of fans, get a fan for your room if you don't have one already. Just don't let it blow right in your face, lol.
If for some reason the night sweats do not improve after a while, you might need to see your family doctor as it could be a hormone imbalance.
I hope it goes away because night sweats are NOT fun! Have a great night! Sleep tight! :)