Need help? Is the USB port on your Windows system disabled?

Last night, while playing a game, I accidentally pressed some combination of keys on the keyboard, and then the keyboard stopped responding. It also beeped a few times with the USB recognition sound, and after that, the keyboard lights went out and it couldn't be recognized. Today, I found that only two of the four USB ports on the first row of the motherboard can be used. When I plug in the third one, neither the keyboard and mouse nor the headphones respond. What could be the reason for this?