Air conditioning sickness

It's too hot outside, and when I'm at home, I feel cold and chilly all day while enjoying the air conditioning breeze, maybe that's why.

Since yesterday, I've been experiencing migraines and I feel a slight stomach ache.

I took one Tylenol yesterday and it got better.

I'm feeling sick again today.

Maybe it's because I only ate cold food, but my stomach hurts today.

I just woke up, and I'm not feeling very well.

Could this be a case of heat illness?

Which hospital should I go to in the Yeongdeungpo area?