My 16 year old daughter is complaining that her chest hurts. It hurts all the time, more severely when she inhales. On the outside, it feels tender and hurts to press on a specific spot under her left breast . She is 102 pds. and 5/4 . She is in good physical condition, cheers, tumbles, etc. She has recently been doing physical therapy for her knee . This morning she woke up complaining of the pain again and said her head hurts and she feels like she s getting another cold.