Allergy to chemicals

Sounds possible. I haven't had that problem, but I need to be very careful about what I eat and have been for many years. An intolerance rather than allergy, and can sometimes just be a general feeling of malaise depending on the severity. Palm Oil being 'hidden' in foods is doing my head it!

I remember some years ago a TV programme that showed up some imported furniture causing severe skin reactions.
So maybe yours has an irritant hidden inside?

I’ve been researching flame retardants today, no wonder we have so many unexplained health conditions they are everywhere, furniture, bedding, children’s clothes and curtains to name a few.
Many are derived from very nasty chemicals and when they degrade they contaminate the atmosphere in the room. Nobody seems to care as long as they pass the fire test.

I'm similar to you Davidhs … swollen itchy eyes, sneezing, blocked nose, headaches etc.
Mainly in relation to chemicals and perfume.
Any cleaning product.

Your new sofa does look a likely subject doesn't it?

new furniture, flooring etc gives off VOCs, volatile organic chemicals and they can and do cause reactions similar to allergies. The gases will eventually go but you must keep the room well ventilated and windows open with a through flow of air

VOCs are dangerous, you can buy air purifiers that will help to remove them and some plants also help to keep the air clean but initially you must do all you can to ventilate that room and not stay in there

VOCs are everywhere in buildings and furniture and are a major cause of being unwell and worse