You could take her back to urgent care and get the anti biotics in a shot too. They can give you some supositories to keep her from vomiting. Some kids vomit when they get fevers, and we had to keep pherenagin on hand just in case or we could not keep any meds in her. You can also ask the pharmacist for tylenol supositories, they are sold over the counter. If you can get her fever down, she might hold down the meds too.
If she seems dehydrated, take her to the ER and they will get her well enough to keep the meds down.
M.