Child Has Flu And Mycoplasma. Done Blood Test. Weakness, Tiredness, Stomach Pain. Should I Be Worried?

I have a 14 year old with the flu and mycoplasma . She has been sick most of her life it seems. She had mono as a toddler and not sure if that is related or not. My concern is that her lab reports show a WBC of 4.10 and a platelet count of 135. The Urgent Care physician told my husband to make sure her pediatrician takes a look at her labs. She has been weak and tired for months and often complains of stomach pain. Sometimes she will eat just a few bites and say she is full or feels sick. Should I be worried or is this another phase of teenage life we will get through? Thank you so much! A.H.