Overheating while running/lightheadness/nauseau afterwards

For the last five months it feels like whenever I run my "internal thermostat" is broken. I overheat and have to stop because I feel like I'm going to faint.  This feeling also happens at the gym.  I feel lightheaded after only a half hour and need to sit and calm myself.  I don't know if it's my diet or what.  I think it might be vertigo because I feel like my head is swimming in waves when I stand still and everything is closing in on me.  I am 32 years old, 5' 11", 167 pounds, in great shape, and have never suffered any major illnesses before.  About an hour afterwards, I feel queezy (though I've never vomited.)  Thank God I know when to stop running.  But I'm worried and don't know what's wrong. I even feel this way at weddings sometime and at concerts. Thank you for your time.

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Hi,You need to have your thyroid checked.Sounds like that may be your problem.The thyroid works like the fan on a car cooling the engine.The thyroid cools your body down in the same way.They will need a blood test to checked it.Good luck.