
I have a list of allergies as long as your arm (and that's only the ones I know about as I develop different ones all the time :rolleyes: :( ), so I won't bore you with them all.
Most of my allergies are triggered by environmental factors, the obvious and common ones being animal fur (particularly cats & horses but some dogs as well) and dust. Exposure to certain chemicals (in household detergents etc) can set me off too. I had a horrible time when we were renovating our current house due to the constant exposure to dust and spores produced by the damp/wet rot that infected the whole house. I honestly felt like I was going to die on a couple of occasions...eyes swollen shut, sinuses totally blocked, throat swollen to near closure etc. On a positive note, I think that period acted as a kind of exposure therapy as my dust allergy seems to have calmed a bit since :)
I have on occasions reacted badly to food. The most violent reaction was to prawns many years ago so I've avoided them since. I do tend to avoid shellfish in general but have pinched the odd mussel (can't resist 'em!) of OH's plate in restaurants and haven't come to any harm so far.... I have experienced swollen lips/burning sensation around the mouth on several occasions. Again, I am 95% sure that it could be attributed to chemicals (in toiletries/detergents/lip balm/lip gloss etc.) and I try to buy only organic fruit and veg as I believe pesticides on certain produce were causing a reaction on occasions.
I have suffered the swollen eyes you describe many times. In my case I was able to eventually pin it down to being heavy handed with moisturiser when applying it before bed or using a moisturiser too rich for the eye area. I would wake up barely able to see out of one eye (or both on occasions). I can't remember who told me that it might be over-use of moisturiser that caused it but when I sought out a gentle product formulated for eyes, the problem decreased dramatically.
I do hope the allergy testing sheds some light on what is causing your particular symptoms. It's no fun having allergies in the first place and even less so when you don't know what is causing them :(