It wasn't quite like this Victorian parlour song, but I arrived to find the organist was absent, and somehow I ended up volunteering to play.
The minister's decision to say rather than chant the psalm was the right one, given that the congregation was also small that day. I don't have enough experience of chanted psalmody to be able to do this without at least being able to play through the chant a few times. The canticles were okay though, because the text is more familiar.
My sight-reading isn't as bad as I thought! But, it isn't good enough yet that I'd really be happy to do that for a "main" service. I didn't do myself any favours with tempo and I might have taken things a bit more slowly, especially as at previous services there I've found the hymnody leans toward a more stately pace. On the whole I think I would be better off playing the first line or even just the starting notes and then singing: people would likely find that easier to follow than an organ or piano. In fact (and I did discuss this with the minister afterward) there's a strong argument for two-note chanted psalms and canticles, and unaccompanied hymnody, with so few people and without the usual organist.
Next time, it would be better to spend more time rehearsing the unknown hymns on the electric piano and less time trying to work out how to turn the organ on... and I really should get around to doing some practice at Christ Church, as a change from the instrument I'm learning on at St Andrew's.