You give the tube an extra sloppy lick for good measure. As the countdown finishes, there's a bright flash and you get sent back 3 seconds in time. Also you are now a Golden Retriever instead of a Beagle...

You remember the white lab. You remember the Scientist coming and taking you out of your cage. He patted you and called you "Good Boy". You wagged your tail as he lifted you into the metal box and then closed the lid. Inside the box it was cramped and there was a sort of nozzle with a small red led light. Perhaps some kind of treat would shoot out of it for being such a good boy. Outside you can hear the scientist talking. "Initiating process. Safeties off." You look at the tube again and flatten your ears. "Quantum state in three, two one