Hello, my name is Dan.
I will do my best to help you, the only stupid question is the unasked one.
Okay, the first thing I suggest you do is hold the power button down until it shuts off.
After that do a pram reset, the instructions follow please do it precisely as I say and then we will get on to fixing the rest of it.
To do a PRAM reset, you need to restart your machine and hold down these 4 keys.
‘Option’, ‘Command (Cloverleaf or Apple)’, ‘R’ and 'P'.
Keep them down until you hear 4 startup chimes.
If you have a wireless keyboard then the procedure is a little bit different.
Use the very same keys but wait until the first chime and immediately press and hold those keys. I recommend getting your fingers ready because timing is critical.
This resets all of the system buses on your computer, USB, FireWire, display, ethernet and your keyboard/mouse/trackpad.
This will correct many faults but not necessarily yours.
Then please tell me just what machine you are using, and iMac, a laptop?