you need to fumigate and fungicide your bed, or just throw it out and get a new one, and wash all your linen in 60'C water, if it smells funny or has fungi growing somewhere, also search carefully, man, bed bugs are the absolute worst, but  they take time to build up and their shit is irritating

also, the room may be involved, possibly the carpet is fucked as well, but for that just a steam clean, test whether window open helps if it isn't in the path of some nasty smoke stack from some industrial facility

in that latter case, you should probably seriously consider getting an air purifier with HEPA and UV, and also, moving

aside from air, linen and the mattress, think about what you are eating in each case it may not be the differential you expect

these things are so annoying i have suffered breathing problems from beds, bedrooms, carpets, fleas, bed bugs, black mold (yes, check what's under the bed)

the absolute worst thing about rentals is how they usually come with shitty furniture that nobody takes care of because it's not their fucking property

god i hate the perversion of the banking system, see how many ways it fuckes you?