Hello, I Have A Question About My Daughters Health. She

Hello, I have a question about my daughters health. She is 10 years old and has frequent bad headaches along with feeling sick to her stomach and stomach hurting. She also has a lot of joint pain. Mostly in her knees and ankles. She has been to the doctor for these things many times. A few months back She had an MRI with contrast and everything came back normal. Routine blood work also came back normal. The Doctor says her headache is just sinuses, her stomach is just acid reflux and her joints are just from growing. I'm worried that these things could be related. any idea what could be going on? or Am I just an overprotective mom?