My daughter recently developed a high fever (103.9). At her DR, she was prescribed Penicillin in which she had an allergic reaction to. I took her to emerg and she was giving Hydroxyzine to control the reaction. Her fever lasted three days but now is only slight (99.9)- she has been grabbing her left hip but I didn't think anything of it until she was just going potty. She grabbed her left hip and started screaming and crying telling me her hip hurts. What is this and should I take her to the DR? She is 2 yrs old.