PADI Advanced Open Water

Yaaah, I managed to get two dives in today to complete my PADI Advanced Open Water I started in the Philippines last year. I found out a few things during the dive today, some good, some bad :

• I don't panic too much when it all goes a bit pear shaped
• Even in exotic locations, the visibility can still be piss poor
• My watch was only waterproof to 30m (although now I could take it to any depth)
  

I joined a Raleigh group that had done their Open Water, and moved on to their Advanced this week. We went to 30ish metres, sat on the seabed and wrote A-Z then Z-A on the slate, and it was all hunky-dory. I thought visibility would improve as we descended, but it was that bad you had to be inches away from someone's mask to see their eyes at times. We then sat around for 10 mins or so.....which seemed to last longer than that. I checked the time on my watch, and it was all ok. An instructor came round counting us off, then I wondered whether we should have followed him. Some more time passed so I looked around to see what I could bang my tank with to attract attention...the only thing being my plastic watch, but it did make a noise.
This went on for a while, the other two in my group wondering what the hell I was doing, but I knew it made sense. I heard the bells from the instructor was wasn't confident enough of the exact direction to move towards it. Eventually my air started to get low, so I signalled to my group we'd surface, with a stop on the way (using their depth gauge as mine was wonky). As I rose from the seabed I kept tapping away on the tank, the out of the blue (boom, boom) my instructor appeared. I signalled to her about my air, then took her second regulator as my intake, then slowly headed up with the compulsory stop.
So I felt ok, and afterwards asked the instructor if I did the right thing, and had indicated the correct stop depth to the group I was in, so I was quite pleased with that. It turns out they were doing a quick search for someone...unless I lost a bit in translation.
On the boat back I checked my watch which had a little bit of the South China Sea inside it. Not good. I rapidly calculated that it cost me the equivalent of a month's worth of the beach hut accommodation in Krabi I was looking at last night.

On the plus side, my navigation dive went better than I thought, despite not having too much on the seabed to use for my natural features navigation part.