Premiere Pro Speeding Up Video

So I recently got Premiere Pro, and its been nice for the 1 day I've been able to use it so far, but today I tried to edit a normal mp4 file like I was doing yesterday, it sped up the footage in any of its previews. (If its in a bin, the source thing, or a timeline) And it does it for anything I was working on, so its not like its a project specific thing, and when I export media the resulting file is normal, so I reinstalled Premiere, and deleted my preferences, (by holding alt + shift when it boots) but it still has the same problem, keep in mind that it must be a universal setting, that I activated today, because now every single file that I preview in premiere now has this problem, when it didn't yesterday.