I've been having heart palpitations for a week out of nowhere. i have propranol for when they get bad. checked out fine before. does this warrant er?

Yes: you need to be seen, and propranolol isn't meant to be used on as needed basis, it can cause more palpitations if stopped promptly, wish you well

Palpitations. : My concern, as it is yours, is that they haven't stopped for one week. People can have history of an issue which causes palpitations, but when they last this long they deserve another evaluation. I believe an emergency department visit is in order.