@Linkat,
A lot of people are allergic to Penicillin, just make sure that it's everywhere noted on your daughter's medical forms in school and at the pediatrician's office.
Yes, Kindergarten kids can be very hypochondriac, I've seen it myself when one kid gets sent home because he/she's ill, all of a sudden the entire class has symptoms. At one time, when I had to pick up my kid from Kindergarten (she faked being sick), there were 6 kids at the nurse's station, all with the same symptoms. At that age, it's still hilarious....