When i get hot and sweaty after exercising or being out in the heat i get a headache, nauseated and a stuffy dry feeling in my sinuses. what is this?

Sweating & feeling: Warm are normal-how the body cools itself . Stuffy nose likely due to normal dilation of the blood vessels. Dryness prob due to more air passing thru nose. Try a saline spray in nose before w/o. The headache may be that you're dehydrated. Drink plenty of water throughout day. Nausea may be due to eating to close to w/o (wait 1hr+), or not eating enough calories. Check w doc if nausea & ha continue.