Learn to blow your nose for crying out loud!

Seriously, I can blow my nose, it's easy, it's something we all take for granted until we have children.  Add autism to the mix and watch out!  My son is almost 11 and refuses to even try to blow his nose, the frustration level surrounding this is through the roof. To hear the snuffling constantly for hours, all day if he has a cold or allergies and is home all day drives me up the wall.  Then comes the clearing of the throat because of all the junk that is stuck back there. If it is really bad, then comes the vomiting. Yeah!  Got to love that right?  WRONG!!!  He gets so much junk in the back of his throat that anything and I mean anything can trigger his gag reflex. 

It doesn't help that Will doesn't listen...he knows what will happen, and the right way to do things...I couldn't possibly have any wisdom from my lifetime of experiences....right?  Grrrr!  Will has thrown up twice today, once upstairs while folding and putting away laundry, the second was from taking his meds this evening. He swallows them dry (I have no idea how he does this!). I asked him to wait, we were going out for ice cream as an end of school celebration thanks to my mom. He refused, took the pills and ran into the other room. I asked where he was going and he told me the bathroom in case they made him throw up. Again, I said "no! Just wait!"  Too late...he had taken them while standing over the toilet, lid down, he gagged and threw up all over the outside of the toilet as I was frantically yelling for him to lift the lid. This resulted in 80% over the seat, lid and back of toilet and 20% inside the toilet (which apparently he had clogged earlier while having a movement and peeing all over his pants!)

First and foremost, I wish he would listen. Then I would like him to learn to blow his darn nose!!!!  (There seriously aren't enough exclamation points to stress this point)

What is it about blowing a nose that is so difficult to learn?  It seems like second nature to me, I put a tissue to my nose and blow. How can he find this so impossible?  Does anyone have a suggestion?  I went to google to help me out...this is what I found:

 http://m.wikihow.com/Blow-Your-Nose

Read number 7, it really made me laugh!!

I had to give him cold medicine AND melatonin to get him to sleep last night because he couldn't breathe. (And prop his head up with pillows)