possible yeast rash

DS has had a rash for over a week. I've tried everything to treat it. (i.e. - butt paste, breast milk, a&d, desitin purple tube, malox, cleaning with warm water instead of wipe) The hardest part is keeping him in a clean diaper. He leaks a little poop when he passes gas (he's very gassy) and constant bowel movements (at least 3 a day). I try my hardest to change is diaper when I know it's dirty. Just now I changed it twice in 10 minutes because he passed a little poop with gas. I'm not sure if it is now a yeast rash or not. It's red with raised bumps around the irritated area.

The office is closed tomorrow and I have no idea when I would get an appointment. Should I take him to our ER to be seen for it? Our ER is in the same hospital his pedi's office is. Or, if it is yeast, should I try to treat it at home first?

Yeast looks like sunburn with blisters and quickly escalates. It is also very painful when touched at all - even with warm water. So I am doubtful that it is yeast. You could try Ilex Paste which provides a waterproof barrier (you put something else on top which you wipe off with each change - the Ilex paste won't come off until a bath). That is the only way that I could get my DS's weeping sores to heal (before we switched to cloth which got rid of them for good).