I experience chest pain and palpitations. I'm still on my way to go see a doctor but at what point in time do I call 911? Like, I've been randomly getting palpitations for a year now. And I've seen several doctors who have said there was nothing. Last wee

When unstable. You should call 911 when you feels unstable, dizzy or like passing out. You need to have some testing like a holter monitor and echocardiogram and some labs including thyroid studies after a careful history and physical exam. Please see a doctor.
Always . Always take chest pain very seriously. There is no wrong call to 911. If you think you need it, call them. In the meantime, always follow up with your health care provider to report your palpiation episodes and keep a personal record of the occurences so that you can give an accurate report to your doctor.