Didnt know you need advice on whether to change your bed
mattress that is infected with bugs. Life changing decision making
some more. lol.
Life must've been pretty easy. Don't forget to remind your mum
to change your pillow case too. 
Bed bugs can be prevented with basic hygiene. E.g cleaning and
changing your pillow cases , the sheets and covers weekly. Putting
it out to the sun and let the UV bake those micro bastards.
Our dead skin will continue to feed those bed bugs, but overall
hygiene helps alot.
Same with your fluffly toys... the sun is thier best friend.
hygiene got nothing to do with bedbugs...........you can pick it
up anywhere or someone go your place and pass to you..........
they don't just appear out of nowhere..........
hotels and cinemas are prime locations to pick up these
farkers............
mostly becoz of all these foreigners coming from shitholes like
India and other 3rd world countries..........