I can remember almost everything about this book except its title. It's about a girl living in a drought and she picks up this stopwatch (i think) that transports her to another world. She meets a purple furry creature that becomes her friend, a baby dragon, and this other strange creature who's been following her trying to protect her. She learns there is a war (or something) going on and someone is trying to destroy the Earth with a device planted at the earth's core. She has to collect a certain number of rods (or gems or something) from different worlds. One of the worlds is underwater and another one of fire. The only other detail I remember is the magic golden dust that heals and that at the end of the book she wishes for her furry friend to be resurrected. Hope someone recognizes it. Thanks!