Sharp chest pains in 6 year old child, anyone else experienced this?

My 6 year old daughter has been getting chest pains for the last 9 months. They are sharp stabbing pains that come on suddenly, last a few seconds and then disappear. Always on the left side of her chest. We’ve been to the drs numerous times, she’s been put on omeprazole which made no difference. She’s been referred to peadiactrics and we finally have an app next month. Anyone else experienced this with there children? It stresses me out and worries me so much 😞