Assuming your using a reputable charging brick and cord I would suggest to clean the phone's System Partition Section Cache Files.
Clear Cache Files from the phone's System Partition Section > https://www.samsung.com/uk/support/mobile-devices/how-do-i-clear-the-cache-on-my-device/ You may need to insert your earphones or hook upto a powered On Laptop or use a Tv's USB Port to access the Clear Partition Section. This may help with lag or stutters as this clears the phone of old/unused or broken cache files.There is also a Repair Apps option in the Menu System too.
Then if needed run the diagnostic tool found in your Samsung Members App.
Ensure all your apps and phone's Software is updated too please.
If the phone is indeed overheating the phone will show a pop up advising of this and in extreme circumstances shutdown.
A Samsung Service Centre can assess your phone if required.
If I can be of any further help then please don't hesitate to ask. 😎
Daily Driver > Samsung Galaxy s²⁵ Ultra 512Gb ~ Titanium Black.
The advice I offer is my own and does not represent Samsung’s position.
I'm here to help. " This is the way. "
