main street bed bug on 09/14/2012

i rented one room in a house where 4 more girls live.i took one room in 1st floor & when i went to sleep,i got bed bug bites.my body started to itch & i had rash in my shoulder, arms, leg everywhere.I threw out the mattress from my bed & bought a new one for me.I informed it to my land lord.The strange thing is my landlord just took the mattress & put it back to one of the closets in 1st floor!! So his intention is, if i'll leave the place, he is gonna put the mattress back to that bed so that w