How can i treat my allergies?

My allergies are making me miserable- headache, fever(sometimes), sore throat, runny/ stuffy nose, basically, it sucks. I'm allergic to wet gr right after it's cut, and pollen. I can't avoid it because it's been raining alot where I live and my school just cut the gr, they do so once every two weeks, and they have a garden for the agricultural cles, and I have to go outside to get to half of my cles. So does anyone know any ways I can treat them and not cost too much money? Money is kind of tight now, so the less expensive, the better.