Man, it's been one heck of a morning for my computer this morning!
When I started up my laptop, it had this virus called "YTAdRemoval" which runs very annoying ads on the websites I visit, including this one. The virus has an extension on Chrome that cannot be removed at all, so I searched my computer to see if any suspicious programs were installed recently but I didn't find any. Then I did a System Restore to a point two days ago, and it did the trick. No more YTAdRemoval!