good afternoon.is it possible that i have some health problem,i noticed that i shivered.I remembered before when i am studying, i shivered too when we are going to report in front. But that was long time ago, Ive finished my studies.Its just okey if i am hungry or tired there are reason that i feel that way,but it was not, even just i am standing or anything else i feel that way too.i don't drink liquor.what do you think what the reason behind of this.?thank you so much