That's what happened to me, went a week with the pain before finally being talked into going to the emergency room.
Well I was put on Aspirin, Beta-blockers, given a nitroglycerine spray yesterday - and referred to the Rapid Access Heart Unit - although the Doctor said don't get too excited about the 'Rapid' part of it's name. So I'm waiting for an appointment to come through - probably not till April? (I was talking to a lady on Sunday, and she'd been to A&E, and her appointment wasn't until the end of March).
The Doctor also told me to stop taking my Naproxen, as it doesn't play nicely with Aspirin.
Personally I'm not 100% convinced it's Angina, I suspect it 'may' be an interaction between Naproxen and my existing blood pressure medication - I didn't have any chest pains until after I started taking that. Obviously the Hospital appointment is to run tests and see if it's Angina or not - so we'll have to wait and see.
I did ask about the pain in my arm/shoulder, as I was stopping the Naproxen, he said to continue taking Codeine as required - although I've managed not to take any for almost two weeks now.
The underlying cause is due to a calcified tendon, with a spur on it (according to the scans) causing damage in my shoulder, and I'm currently waiting for a physiotherapy appointment (25th March) to evaluate possible treatments.