I was raised in Bavaria around tons of farms and I had terrible allergies to pollen and some others as well. My eyes swelling shut and stinging, breathing troubles and a runny nose were common in the summer time for me.
Now I don't have any problems with the above symptoms, possibly because I have a dog or I've grown out of it. Benadryl hasn't helped me in the past because i was usually dead asleep on the couch. There are studies showing that being around dogs helps with allergies so maybe give that a try.