You sink below the sand, thoughts and form blurring as you're dragged down. You try to cover and protect your head, but can't reach that high. Despite the sand and your mouth being open, it feels wet. Your entire body feels wet and unsteady as you drop down into some sort of den, though you're too disorientated to notice details.
A tail rises from the goo that's covering you- no it is you now, your insides no longer flesh. Scales start to dot across your body, and claws- ones made for digging through the very sand that's swallowed you- emerge from hands turned into paws.
You no longer feel worried, though you feel a little shy when your new packmates approach to greet their new sibling.