Suggest Treatment For Severe Heart Pain

My daughter is nine years old. She complains that her heart hurts or that it flutters or feels weird. Sometimes this is accompanied with vomiting and the shakes. Sometimes she says she feels like she can’t breathe right. She sweats a lot in her sleep or if she is active always seems to be a lot more than other kids. She is constantly thirsty. She has been to see a gastro, pulmonologist, and a cardiologist. She has been checked for asthma and was fine; they put her on an inhaler for when she is active. She had an EEG which was normal. She may have a mild reflux but not severe. She was also checked for Diabetes and came back negative. I feel like we are missing something help.