Sometimes when I play tennis in the hot sun (90-105) temperatures for a while (2-3 hours) I get the chills, especially in my arms…the hairs on my arms stand up… and the chills come maybe just once or twice and then go away. are the chills a symptom of some sort of heat stroke/heat exhaustion? I don't have any other symptoms besides those that are common when one exercises a lot. oh and later at night I feel very hot and sweat sometimes i even get hot flashes. I do and drink a lot of fluids while playing of course