You can try some software like Recuva or PhotoRec. If it’s a partition data corruption problem TestDisk http://www.cgsecurity.org/wiki/TestDisk might fix it.
it sounds like you may have corrupted the partition. when you connect it to your pc, can you see the drive in disk management? if so, then you may want to get a hold of a partition recovery software. if you have corrupted files, you won’t be able to recover those, though.