Rosy cheeks

My 4 month old has very, very rosy cheeks as of earlier this morning. Both cheeks are uniformly red and feel just as smooth and soft as the rest of his skin. He has been drooling quite a bit and we've suspected that he might be in the early stages of teething. But, if the cheeks were red from drool, wouldn't they feel rough and irritated? He has also coughed several times today. Probably no more than 10 times total, but my husband thinks the drool is actually getting him choked up and causes him to cough as it doesn't sound raspy or anything...it just sounds like I do when I choke on my own spit.   He's in a great mood and does not have a fever. As a matter of fact he's kicking me in the side and laughing his head off as I type this.....Any suggestions on what is coloring my babby red? ;)

is it too hot in the house?

Thanks for your reply! I don't think it was, but we cooled it down just in case. They're now starting to actually get a bit dry so I'm pretty sure it's the drooling from the early stages of teething.