Stropwen, since for whatever reason you needed to remove your post, it makes it hard for us to help you. But because you've answered my question about whether this was a try dive or discovery dive by saying you were enrolled in a full certification course, that raises other questions. So I've tried to recall what you told us so that I can ask those questions. What I remember is something like this (please correct me if I've misunderstood). My questions are in blue following the various items.
There were 15 students and one instructor in the class.
Was the instructor using any assistants, DMs, for example? The reason I ask is because when we have large groups, we can increase the ratios by adding assistants to help us keep track of everybody and ensure safety.
Your class was delayed 3 hours and you waited outdoors in the rain during this time.
Was the entire class waiting? Did you perhaps misunderstand the time you were to meet? Or did the time change and maybe you weren't informed? Is it possible there was some kind of misunderstanding?
You geared up, but apparently did not put on a weight belt.
Did you not do a pre-dive safety check with a buddy as is your responsibility? Didn't the instructor ask why you didn't have a weight belt on?
You entered the water and because the instructor did not demonstrate the method for descending, you had difficulty.
IIRC you said you spent ten minutes trying to get down. This seems like an awfully long time. Surely somebody would surface to help you when you were taking so long. Could you see the group below you waiting for you? What were they doing all this time?
When you finally managed to descend, you said you sank like a rock, but you could not stay submerged.
If you actually did sink like a rock, that means you had enough weight despite not wearing a weight belt and didn't really need any extra weight in order to stay down. Generally speaking, these kind of "float up to the surface" ascents happen when students are stressed and hold too much air in their lungs. Were you feeling stressed?
Eventually the instructor followed you to the surface and told you to stay on the bottom.
Who stayed underwater to care for the safety of the remaining students?
The instructor descended back to the group waiting at the bottom and left you alone at the surface.
Was there somebody on the shore watching you to make sure you weren't in trouble on the surface?
You exited the water alone to retrieve a weight belt, you put it on, and then you re-entered the water to descend.
How did you know how much weight to put on the belt? Had you simply forgotten to put it on, or did you think you didn't need any weight initially?
You completed a total of only four skill demonstrations (weight removal/replacement; alternate air source use; regulator recovery and clearing; mask flooding and clearing).
Did the other students complete other skills while you were stuck on the surface, swimming back to shore and finally getting down to the bottom?
The maximum depth of the dive was 40 ft.
This is the typical depth for a first dive of a series of Open Water dives. How was the dive conducted? Did everybody just mill around or did you follow a route or do a circle or go see some artefact and swim back or what? Were you assigned buddy pairs? Who was leading the dive?
There were no pool or confined water practice sessions prior to this dive.
This is just amazing. I hardly know where to start with this comment. Did you miss class sessions by any chance?
At the conclusion of a single open water dive, the instructor indicated that he would issue your certification.
This is also amazing. Are you certain that he wasn't simply going to LOG the dive? Are there no other dives scheduled for this course?
