Just irritating

Why do some people when they get a head cold say "I have a cold" and others say, "I have a sinus infection"?
OK, we all know that I've been 'blessed' with medical problems, so I've done my fair share of googling medical terms. This of course makes me almost like a doctor, right? OK fine, at least a nurse.
When I talk to someone and they do not have a head cold and then the next day they are completely stuffed up, I would assume they have a HEAD COLD. Correct me if I'm wrong, but doesn't a SINUS INFECTION mean a head cold that doesn't go away? OK, maybe it isn't that simple, but can you go from not having a cold one day to having a 'sinus infection' the next day?
And the fact that this irritates me is also irritating to me.

Do you know what else is irritating?
Standing in a long line in the store and having the woman in front of me turn around and look at me and then grab a pamphlet out of her purse.
But then, she doesn't talk to me, she bends down and starts talking to my son.
She starts telling him how there is no one in the world like him. He is such a very special person. No one else has all the special things inside them like he does. God loves him just for being himself. (Which, I think might have come from Mr. Rodgers, but anyway...) Do you know who GOD is?
She then proceeds to hand my son the pamphlet and tells him to ask me to read it to him.
Now, I am a Christian. I believe in God. I don't need the woman talking to my son. What if we were atheists? Anyway, I just thought if she wanted to talk to ME, fine, but my 4 yr old son...irritating.

Another irritating thing? Making an ass out of yourself.
As I was jogging up the stairs to get Miles out of his bed, my foot slipped and as hard as I tried to catch myself, I landed face down on my nose. My nose.
Luckily it didn't break, but it swelled and was really REALLY sore. The next day I proceeded to wake up with a cold. NOT a sinus infection, but a cold. Blowing my already sore nose isn't so much fun.
Irritating.