It sounds like it was just a mistake. But Rrudnic is correct, you can't catch your own throw unless someone else touches it beforehand. Incomplete passes/bad throws happen all the time, and that's just part of the game. Also, just for clarification, drops do not go back to the thrower unless the mark knocks it out of your hand, in which case it's considered a "strip."
This is actually incorrect. If a thrower drops the disc (i.e. loses possession while not in the throwing motion) and they regain possession before the disc contacts the ground, it is considered to be the same possession.
However, if they release the disc as part of the throwing motion (a throw or a fake) and they regain possession before it it's the ground, that is considered a turnover.
For strips, you may call either "strip" or "foul."