Hi Blueanchor,
In regards to your original question as to what to do - my suggestion
wouldn't be to complain about the captains negligence, but to consider going back to the captain and discuss what happened with an attitude to learn instead.
For insance, it may be helpful to find out why he wasn't there in the first place, and what his advise is for you if this situation ever happens again. What was he expecting from you, and what were the circumstances that happened to make him move away? (So you can look for similar circumstances in the future and choose not to dive off the boat if you think it may happen again).
Who knows, once you know his side of the story too, and the reasons he made the decisions he did - you may even agree with the captains decision.
Any captain worth his weight will probably be willing to talk to a diver that has had a bad situation on his/her boat - especially if that person comes with an attitude to learn from their experience.
And congratulations! You've entered a group of divers who have been in a situation that was way outside of their comfort zone, and you have dealt with it. Many divers can have ample dives under their belt and be quite confident, but have never ran into a situation where they're out of their comfort zone. IMO, It's the situations where you're outside of your comfort zone and how you deal with them that makes you experienced - not how many dives you've done!
You stated in your original post:
We were in a panic. I blew up my safety sausage and waved it like a madman.
I question whether you were in a panic as opposed to being extremely frightened. The difference is that someone in a panic pretty much loses all control. (You may remember what a panicked diver looks like from your O.W. course).
According to your story, you were able to blow up your own safety sausage and think through the situation -even though you were really scared and feared for your life. Your buddy thought to watch out for sharks. Whilst looking for sharks is pretty much unneccisary - you or he didn't know at the time. You worked together and thought things through to the best of your knowledge - and it shows to me that you were thinking. Panicked people don't think. You did well - congratulations!
I recon there are now two paths you can take from here. You can let this create more problems (looking to blame someone, get more worried, quit diving, etc)
or you can look at this as an opportunity to learn more about boat diving and what to do in different situations. There are some good informative replies to your post (if you can take the time to sift them out from the others) that may also help you learn from this experience.
Hope this helps...
Roughwater