It very well could be. Sounds like what happens to both of my girls. Our ped (new) has me giving them a small dose of children's zyrtec on high pollen count days. It's helped a lot just in the last week. I'm noticing a lot less snot, their eyes are clearing, and L hasn't complained of a headache in a few days. (That was becoming a regular occurance.)
Allergies can lead to infections. :-) Such as ya know, raging sinus infections lol OR in the case of my girls, ear aches. The last few times it's happened I either treat with drops or just let the fever run it's course. I know L's tubes will prevent her from getting seriously sick with them.