Hi Ada,

Hard to pinpoint these things, isn't it, but I'm guessing that if you were OK with your own belongings before you moved, then it may be something in the fabric of the new place (often happens).

3 hours of strong sunshine will kill dust mites, so get someone (ideal for the boys to do) to take all your cushions, blankets, duvets, pillows etc - mattresses and sofa cushions too - outside for a while, just to be on the safe side, and turn them to face the sun now and then. It works and couldn't be cheaper, lol. The Chinese hang their bedding outside as a matter of course...seems to come naturally.

If you do think there could be lurking mold or whatever, you could use a clear sealant to "paint" over the area - this site has all sorts of safe anti-allergy stuff:
http://www.alerg.com/

Do you find antihistamines can make you feel nauseous? I do, phenergan's the worst - I mean it works great on sneezing-type allergies, but then I just feel sick as a dog.

If it's not one thing, it's the other, huh?
all the best