@KylieWaldon this is a shed moult from a huntsman, it's how they grow and get bigger. Since invertebrates don't have any bones or internal skeletons, they have to moult their exoskeleton in order to grow
I've been bitten by an adult female I. canberrana before and apart from a bit of pain and the tiniest of swelling, it wasn't bad. If you're worried, use an ice pack on the bitten area and if symptoms persist, seek medical attention