I can't breathe really well. I feel the air too hot and litte?

Ok, it all started today while I was playing basketball. It's summer and today is the first day in two weeks that had scorching heat. I stopped playing when I felt tired and then I couldn't breathe well. I felt the air too hot and too little. I can take a deep breathe but I feel the air entering my lungs small. I have no chest or heart pain. What could it be? When I drunk some cold water I felt a little better but I still can't breathe as fine as before. Any ideas what it is?