The only reason your video is playing upside may be that when shooting it, your phone was in an upside-down position, and you didn't realize it. You see, this problem is actually very common, where you find people recording while their phones or cameras are in the wrong orientation. But it's an easy fix though! You can rotate the video with AVS video editor, or iMyFone Filme, which is also a very good tool for this kind of stuff.