Misty -
Don’t beat yourself up so much.  I always find it harder to concentrate when the kids are sick and I end up writing everything I gave them and when so I don’t forget.  Also when I talk to the doctor then I can go through my list otherwise I know I would mix it all up.

1st question, are you sure it is .5mg?  My tabs come in 5mg.

Double Dose...  1/2 @ 8 (2.5mg), 1/2 @ (2.5mg) 2, 1 @ 8 (5mg)
I would keep it doubled for a couple of days, at least until you see some improvement.  I tripled while at the hospital, doubled the day after we came home and then went back to his normal dosage. 
(I am not sure if I answered your question or not)

It is actually good he threw up because he was able to get some of the phlem out.  This should make you feel better too; coughing is good that means it is moving.  When I took Billy in he wasn’t coughing so the phlem was blocking his air.  The better he got the more he coughed and his Oxygen level went up.  I sucked his nose out a lot and used saline drops prior to the sucker.  I also ran the humidifier.

If you just want to set your mind at ease I would call your ped. and tell them you want to bring Blake back in and have his Oxygen level tested.  They probably wouldn’t even need to make an appointment.  This way you will at least know if he is getting the Oxygen he needs and if not then you can prove to them he needs to be treated more agressively.  Is he wheezing?

Stacy