(1) Go and have a shower, wash yourself and pyjamas, and hang them out to dry.
(2) Some people wet the bed all their lives; others till they're in their late teens, others stop when they are pre-teen. Unless you do it purposely, there's nothing to be ashamed of - its "natural", and a part of growing up. But if you're worried, consult your parents, and maybe they will suggest you get checked by a doctor to see if there's anything physically wrong.
(3) Look up the internet in a search engine or Wikipedia and get to know something about it.
Hope that helped - best wishes!
take them offf and put them near a fire to dry? and put a new pajamas on hope this helped