Let me just relay a quick story that relates to yours...somewhat.
The day of my open water cert in the ocean, we were told by our instructor to suit up, get into the water and wait on the towline behind the boat while he took the first group down. There were three of us that were waiting for the instructor snorkeling on the surface of the towline. For whatever reason, the person behind me (who had on a Scubpro Classic, weight integrated BC), started to argue with herself about how her weights werent properly secured. Now I know that we all checked each other and ourselves before we plunged into the water, so I wasnt quite sure what was going on. As I turned around, I could see her fiddling with her weights with her snorkel in her mouth becoming quite frustrated. This was where the situation turned for the worst. It seems that her weights became unlatched in the BC while she was floating on the surface (not quite sure how) and it appeared that her frustration was quickly becoming panicked. For what ever reason she spit out the mouthpiece of her snorkel while fidgeting with the weights, which opened the advantage of seawater intake. It was a short moment later that she did manage to swallow some seawater that sent her into a coughing spree. As this occurred the student diver behind her (I'll call T) and I came to her aid as we noticed the change in the situation. As T reached her, she became quite belligerent and said to stay away. It was quite obvious that she was having not only equipment problem but was accelerating herself into a full-blown panic. T (who now is my diving buddy) swam up to her first, took her by the BC and with a stern voice said, "Let me help you," as she was saying to stay away from her. T then firmly grasped her BC moved closer to her face and said, Let me help you, relax, and calm down. It seemed after few more convincing statements that she allowed him to help, which fortunately calmed her down enough to finish the rest of the dive.
The funny thing about this story is that when we completed the dive, we were joking about the mishap on the boat, and I made a side comment on how she was panicking over the situation...and she said that she never did...
Food for thought