Difficulties with turning off laptop after fall

Somewhat heavy gaming laptop fell to the floor (~50 cm fall). It went black the second it hit the floor. Oddly enough, I didn't manage to restart it until I connected it to a power source. Everything seemed to work fine, including running on battery power, though the fall seems to have cause a small amount of lightbleed on the screen. Nothing serious.

However, when I tried to shut it down again, it immediately restarted. I managed to solve the issue by disabling Fast startup. What might have caused the need to disable the setting, and should I be worried about some additional hidden problems?

(Edit: to be fair, initial turning on difficulties might have been a coincidence caused by insensitive power button)