It’s up to you whether you feel comfortable to tell your dad or anyone else that you have a yeast infection. Yeast infections are very common among young and adult women (and they are not sexually transmitted), but not everyone knows that. If you cannot see your health care provider or get medicine without telling your dad, then you could explain that it’s common for girls and women to get yeast infections particularly around the time of their period. If you haven’t seen your health care provider yet, make an appointment to make sure that you get checked so you can get the right treatment and feel better soon!