My 7 mo old has her first diaper rash. We've been use Earth Mama Angel Baby Bottom Balm for preventative care on occasion. I used it today when I noticed a small splotchy area. It's gotten bigger so I am wondering a few things since I'm new to this problem-

What else do I do to help with healing?
How often do I apply ointment?
When do I try out a different one?
She's been fussier today - do rashes sometimes cause that?
I gave her a few bites of yogurt yesterday, could that cause it?