If you feel unsure go back to the doctors, you know Izzy better than anyone. If she's still not 100% it wouldn't hurt to get her checked out again....I've found that an innocent cold can turn quickly to an ear infection or worse. I find that my two monkeys cut there food back when they're sick and tend to drink more, I always let them have powerade as I figure the glucose will help them get back on there feet. If Izzy's still drinking formula I wouldn't be to worried, mine wouldn't touch there milk when they get sick!
Anyway I hope Izzy's better soon!
Snoopea