My guess: In tabletop, when you perform a short rest, you can choose to use hit dices to recover hit points. You can use as many hit dices as you have levels. Once you no longer have hit dices to recover hit points, you have to do a long rest to recover them. In game, when you do a short rest, they automatically spend hit dices so your characters can recover hit points. My guess is you'll have as many short rests as you have levels. So, if you used a short rest and then it was no longer available after that, you may have been level 1. Am I right?