Heat & High heart rate
Does anyone suffer from a high heart rate while in enclosed areas with heat and no ventilation?
My heart rate usually goes up could reach up to 130/140 on my watch
I feel nauseous and as if I will faint
Is that only me or a common MS thing?

It could be but it could also be something else. I would get it checked out by a doctor. That's one of the issues with MS when we get a new symptom - is it MS or not! All the best