You were "duped" into installing "adware" from somewhere other than Adobe. There are several thousand "fake" updates out there, from as many sites. Many of them use Adobe logos in violation of international copyright laws, to fool unsuspecting visitors into downloading everything from annoying "adware" like you now have... to outright system-destroying viruses.
Download TDSSKiller from Kaspersky. It's free. Run it to find the offending software. (It may or may not... the "mice" are still a step ahead of the "trap" in most cases.)
Go to your Control Panel and look for ANYTHING that you don't remember installing in the last few days, especially from "File.org", or anything that mentions "download" or "optimizer" in the name. Uninstall it.
Lastly, bookmark these links:
They are the FULL installers for Flash Player. ONLY use them for downloading updates.