All I can say is "Well done"; you kept your cool and nobody panicked.
I have dived PG several times and know the site in question pretty well, in fact it's probably my favourite. The currents there certainly do rip along some, with up and down currents also present depending on the tide at the time of the dive, the vis can sometimes be a bit ropey too.
On a recent dive in the Maldives, me and the group I was with got caught by a really strong up current on one of the channel dives. Me and my buddy managed to cling on to the bottom but almost everybody else got blown up almost to the surface, I can still hear the symphony of computers as they disappeared (meep meep meep meep), most aborted the dive and luckily nobody got bent as it was still pretty early in the the dive.
Me and my buddy had to do spiderman impressions to try and traverse the current until it was going horizontal, we then let go for one of the most amazing drifts I have ever done with huge trevalley, tuna, schools of chevron barracuda, and all sorts of other interesting big stuff.
Our total dive time was 57 minutes and when we surfaced the boat was a speck in the distance, and we were in a shipping channel. Though we had four SMB between us (one orange and one yellow each), whistles, as well as strobes and heliographs, it still took us fifteen minutes to attract the attention of the boat.
I bought myself an air hammer from my LDS just as soon as I got home...that thing is loud enough to make your eyeballs bleed, so it ought to be able to attract the attention of the sleepiest boatman.