Interesting. I'd actually been qualified for nearly 2 years when it happened to me. In fact, of the 4 flights I took, there were emergencies on 3 of them! Rather strangely, I was reading Holiday SOS by Ben Macfarlane at the time (a book about the life of a flying doctor), when Case 5 happened. The other 2 emergencies were just people who had vasovagal syncope episodes (fainting) and so I didn't really need to do much, but each time I still got upgraded to first class and given loads of free stuff!
From speaking to colleagues who have also heard callouts onboard planes, I find it shocking how many people ignore it as they are too shy of exposing themselves publicly, even though it may be a potentially life-threatening medical emergency. If you are ever in this situation please answer the call!