Allergies?

The ONLY thing I dislike about Spring are allergies. Today I told someone that I think I have allergies and she asked me what I was allergic to, and it got me thinking... I have NO idea what I'm allergic to, I just know that I get a really bad runny nose, a headache, and itchy eyes around this time of year.  So now I'm wondering if it just happens that I get a mild cold when the seasons change. Then again I know that William gets allergies because he will come home from school with a runny nose and red eyes. And I don't know what he's allergic to except amoxicillan.