My 5 year old had a temp of 101.3 taken under the arm tonight should i call her doctor tomorrow?

Good idea: Make sure she is staying hydrated. If you have any concerns about waiting until morning you can call her pediatrician. The on-call doc will be able to discuss her symptoms with you and give you the best direction.

Probably: Other than fever, if she is behaving OK and is eating and drinking she should be fine.

You can: Fever can be present with viral or bacterial infections. Typically with a viral illness the fever resolves within 48 hrs, Typically we would recommend to see the doctor if fever persists for more than 2-3 days. Are there any other symptoms? If there are any other symptoms such as vomiting, headache, difficulty breathing, irritability, then need to be evaluated sooner