Just playing games wouldn't cause such problems. I do that very often. Maybe, some app might be causing the device to crash, that would also explain the slow charging and overheating.
We apologize for the inconvenience caused. Regarding your concern we would suggest you to visit nearby Samsung Service Centre in order to get your device physically inspected by the Service Engineer. Please find service centre details in the link provided -http://www.samsung.com/in/support/servicelocation
Be sure to hit ♡ when you find an answer that works for you. For Further assistance, you can get in touch with us via Live Chat option by following- http://livechat.support.samsung.com/Customer_new/IN. You can also connect us via Samsung Members web community by following mentioned url-https://community.samsungmembers.com/en_IN#/
things i have suffered after the update till now is
random restarts did everything you name it still the same issue and when you turn on ultra saving mode on note 8 you cannot call anyone tried swipe to call many times but can't make a call amd when u try to turn off the ultra saving mode it tends to get stuck on turning on biometrics and then we have to restart the device to make jt work properly again
