This, of course, can't be. The biggest and most pressing one is the processing plugin-- I can't access any of the vector processing tools. I recently upgraded to 2.18.13, which was released only a few days ago, can that be the issue?
BTW, if it's useful to anyone, the workaround solution I came up with was to uninstall python and qgis and re-download from this site: trac.osgeo.org/osgeo4w instead of the QGIS site. I hope it helps