I see what looks like two mounted drives
Actually what you see are two directories -- that may be used as mount points, but then, pretty much any directory can be used as a mount point. The ones in
/media are conventionally used for fuse automounts (ie., those for non-privilleged users).
mount | grep pi/media and see how many lines of output there are. If there are none, or only one, the data in the other (or both) directory/ies is just plain data that's in a directory; likely it ended up there by mistake when there was nothing mounted.
If this is a bit confusing:
- A mount point is a normal directory.
- That directory may contain data.
- If you or the system mounts a storage device on a directory that contains data, that data becomes inaccessible while the mount is there. Nothing bad will happen to it, however.
So, if one day I assume
/media/foo has a USB stick mounted on it, and I copy
file.c there but there is no stick mounted there, this is not a problem. If later there is a stick mounted there with those files in it, these are separate copies from what was in the directory before anything was mounted on it. If later I look in that directory when I know the stick is not mounted, they will still be there, which is a clue that at some point (check the file modification time w/
stat) I copied files there by mistake.