It's possible you have picked up a nasty, but as a first step I would suggest you try starting in 'Safe Mode' and using the Windows repair system to revert to a date before you downloaded this software. This is quite easy to do.
Switch your computer on, and when the BIOS screen appears ( that's the first one, the one with the manufacturer's logo plastered all over it ) press the F8 key a couple of times. This will switch you into a black screen with white text. At the top there is an entry 'Repair Windows'. Use the Up and Down arrows on the keyboard to select this, then press the 'Enter' key. This will take you into the repair screen.
Let it do its thing. It may well repair your system, if it does great. If it doesn't, it will ask if you want to use 'Windows Restore' to restore Windows to an earliier point in time. Click Yes, and from the list of restore points that will appear, pick one that dates before you downloaded this software. then click 'Continue' or whatever the positive wording is. It should eventually come up and tell you the restore worked and Windows is restarting. it should then start normally.
If it doesn't, then repeat the process, but this time select 'SafeMode with networking' and download the Malwareytes scanner from here :-
and run it, following the instructions about updating. This will tell you if you are infected, and whether or not it managed to resolve the problem(s). If it did, again, great. If it didn't, then post back here in the section 'Am I infected ?' and someone with expertise in that area will respond. Just follow their instructions exactly, and if you don't understand what you are being asked to do, post back for clarification.