i'm so sorry to hear this...
as for the doctor....i really don't know...
but since she's not complaining about anything else, like sore throat/pain in her ears, maybe it's just a virus....
i guess you're going on the 7 day cruise, so i'm sure she'll be better in time to at least enjoy some of the activities...
if you are on the 7 day cruise, then you would be able to see a doctor today when you reach orlando....yes?...
if you're staying on property at disney, you can ask the front desk to call a doctor for you who will come to your room...
or else you can go to that walk in place that's right near WDW....i think it's called centra care or something like that..
when my daughter was sick, a doctor made a 'house call' to our room (i think we were at the yacht club that time).....he was an excellent physician....i was quite impressed....
so if you do have a half day in orlando, perhaps you could do that......if the doctor suspects ear or throat, he/she would be able to prescribe antibiotics before you get on board...and if it's just a virus, you'll know before you get on the ship...