It's down to the individual GP practice to decide what training their receptionists should do - some don't seem to offer much, or run any refresher sessions for receptionists who have been in post for some time.
Some receptionists have had the fear of God put into them by grumpy GPs who have barked at them in the past for interrupting them to check whether a caller is an emergency or adding too many extras on the end of a busy surgery list.
Lots of practices have a list of questions receptionists should ask to try to pick up anyone who needs immediate attention - because the poster who talked about chest pain was right, in a very few cases people who should really be dialling 999 call their surgery instead (after all, they ain't doctors).
Tricky issue is where you draw the line - because as someone posted further down, receptionists can't diagnose at all, much less over the phone, and shouldn't be expected to.
It's something a few people are taking an interest in so hopefully the message will go out to practices that there are ways of organising surgeries/phone calls better to ensure patients who need urgent attention get it, and all patients get a better service.
But in the end, each surgery is an independent small business and does things its own way. If you are pissed off, write to the practice manager and explain what went wrong. Otherwise, nothing will change - the GPs and manager won't know that you couldn't get help or the receptionist was rude or their systems aren't working.