1. I was able to burn my skin on my hand like this, and also the plastic encasing of the tube melted. I think it was because of the lack of proper ventilation. So, it's best to take another approach and try not to sleep with it against your skin. Put it near you, and make sure it's ventilated and not covered by your blanket.
2. If you read the guides for any of the overnight protocols, you'll find that we recommend NOT putting the tube beneath the bed-covers but outside them. Cooling depends on good air circulation.
For more details, please check the link: