Battery issue

Hi everyone!

I recently bought iPhone 15 pro, but I have some problem.

While sleeping I taking off my phone under a pillow. After I'm waking up, my phone is low on battery and hot. There's no any application that utilise batteries phone and sleep focus is turned on. A battery and phone temperature is ok if I leave my phone on a table or somewhere else. Maybe someone have some thoughts or had the same issue?

Thanks in advance