I don't know if this is a bug or something I should know about. I was trying to battle in the coliseum with my pet Chusaii for the plot, and the site was all laggy and there was a connection time out or something. Well I go back now, she has full health, is full, and happy, but now when I go to challenge an opponent it says none of my pets can battle. Is her battle still going on, or is this a bug that I should submit to the subeta team?

Check to see if you still have a battle going on via the statistics page. There, you can choose to either finish the battle or withdraw (withdrawing does count as a loss).