Well, ironically, hay fever is not from hay and it doesn't give you a fever. If you have body aches with a fever, it is more likely to be from a virus like flu than from a virus like a cold; colds don't usually involve body aches. Flu tends to come on suddenly and a cold tneds to build more gradually.

If you have hay fever like grandma roses said, you wont get a fever. A complication of hay fever, however, is an infection. You need to see your doctor asap, explain to him your running a fever and he will most likely (or at least should) get you in there rather quickly. Unfortunately you can get serious damage from infections in your sinus cavities, they can quickly spread to your ears, through, brain, lungs and lymph nodes. Don't wait on this one call today. The symptoms of allergic rhinitis (hay fever) are: Prolonged, sometimes violent sneezing. Itchy, painful nose, throat, and roof of mouth. Stuffy, runny nose. Postnasal drip, resulting in coughing. Watery, itchy eyes. Head and nasal congestion. Ear pressure or fullness. Fatigue. These symptoms are often seasonal. Call Your Doctor If: Your condition becomes so severe that it interferes with your life and you're unable to control it with over-the-counter medications. Steroids, usually a nasal spray, can also be used but are only available by prescription. A secondary infection often develops in congested sinus cavities; signs are fever, facial pain, a yellow or green discharge, postnasal drip, halitosis, and sinus or tooth pain or tenderness.