your body temperature increases during exercise. there are many other factors that effect body temperatures from being perfectly regulated. Once you know this, you can take the appropriate action to cool down before going into an establishment. Hydration, light clothing, rest, shade, fans, airconditioning will all bring you down to normal temperatures quicker.
It happens, find a cool place to sit and relax until you feel comfortable. If you are in a spa, you were going to take off your clothes anyway so start with the shirt, shoes and socks. Nothing like a cold floor to bring your body down to earth!