Strep throat in 14 month old breastfed toddler unheard of?

My pediatrician told me it was very rare in breastfed babies under 2, yet here we are! I was sure it was an ear infection and a GI bug. My daughter spiked a temp and started vomiting on Friday. I wouldn’t get it down below 102 despite cool baths and alternating Motrin and Tylenol. Went to ER on Saturday morning, they diagnosed her with an ear infection and sent her home with antibiotics and not further testing. Daughter kept throwing up antibiotics and most food throughout the weekend. Temp stayed above 101 while medicated and we finally got to the pediatrician today who tested her for strep. Doctor said he wanted to test just to be sure even though he doubted strep because of age and her being breastfed. Why is this so uncommon in breastfed babies in this age group? I should have asked, but maybe someone here knows? I’m just furious with the hospital for sending us home so quickly. From what I read, untreated strep could lead to way more complications and who’s to know that was the right antibiotic anyway. Anyone have any experience with strep in a baby this young? Is there anything else I could be doing for her?