PC really slow after OC and then uninstalling it

I have a 2080Super with a i700, im a complete noob at this so sorry if i don’t make sense i overclocked my pc today with afterburner to about 120mhz? for the core and 800mhz for memory and it was ok for awhile but i noticed it started decreasing performance so i put everything back to default and uninstalled afterburner and it completed messed my system up, it literally takes 1minute to load any app up i don’t know what to do ive went into bios to change settings back to default and it still takes ages for anything to load