Correct, just 2 transactions for the same bitcoin. Both show up at their destination like any other bitcoin would, but only one is confirmed and the other one disappears (remains unconfirmed forever). This customer waited till he saw it in his blockchain to leave, then as he's driving away I accidentally double spended him and his coins were back in one of my wallets. I called to explain, mostly since I've never seen that before, and sent it back to him.

Due to the events of last night, I will be waiting for 1 confirmation from here on out.