I get the same thing..there no reason for it at imes it just happens.
I try to think about something completely different to take my mind off.
I will think about something really cold...try and remember the last time you were really cold and it was painfull it was so cold try and put yourself there and remember what it felt like shivers and all.
Try and cool yourself down by puting something cool on the inside of your wrist next to the vain. GFor example a glass of water, can coke, or even just something metal, like the metal on you chair or metal on a table in front of you place your wrist on that cool surface and it should cool you.
Tell yourself that the people/persons around you are the ones who should be embarrased, they are in their underwear, they just farted in public, they have toliet roll stuck out their pants.
Oh and well my fav is...don't ever wear warm clothes, wear thin light weight never thermal clothing and always take your coat off etc when you ever a room etc the cooler you are, the less likely you are to go all hot and flustered.