Hi
Well for a start.
If you have a restore point that's not too old but before last night try and go back to that.
You could try...
Run Malwarbytes, and CCleaner.
Defrag your hard drive, I use Defraggler, it works great and after the first time you can just defrag the files that need it.
Run SFC /scannow from the elevated command prompt.
It's hard to guess what can cause this but this will attack several of the possible causes.
That's all I've got but someone else will probably have other suggestions.
Mike