I also don't want to spoil, but I think that in the talk given by Lord Asriel to the college, he raised the possibility of there being "many" worlds. But you are getting too far ahead (several books ahead.)
The daemons probably weren't explained very well. Children's daemons are not fixed. They are not permanent and can change shape. They become permanent when the child becomes an adult. This is important to the story so it isn't good that it wasn't made more clear.
The daemons probably weren't explained very well. Children's daemons are not fixed. They are not permanent and can change shape. They become permanent when the child becomes an adult. This is important to the story so it isn't good that it wasn't made more clear.