Run to a stall, forgetting your bag

Panicked, you turn around and bolt for a stall, quickly closing it behind you. You hear a girl walk in. Without anything else to do, you sit on the toilet. Clearly just here to fix her makeup, the girl puts a bag on the counter. You hear her pulling out what sounds like lip gloss, but can't quite tell. She speaks up.

"Um.. is someone in here? There's a bag on the counter..." You keep yourself from smacking your forehead in frustration. Of course you forgot your backpack. The girl continues. "Hello? Is this someone's?"

You can't lose that bag, but at the same time you don't want to chance the possibility of having to step out into the open with no pants on...