Sorry to read these accounts folks. Physical issues aside, keep in mind possibility of environmental drivers eg. dust, cleaning chemicals, allergy to soft furniture, mould spores, bedding, poor ventilation, bathroom n kitchenwaste stack and local waste pipe / bad air leaking into home. I was ill in halls at uni years ago with bad sinusitis for 6 or 7 months, GP treatments did nothing and I later discovered in my room I had a cracked greywater waste system ventilation riser pipe behind a wood panel. There was no major particular strong odour giving it away just the constant exposure, it must have been that as I never had issues like that before or since.