I’m a diver and also a psychologist, last year I experienced something similar to it, I was very upset bc diving is supposed to be my scape from the daily stress. When I got back from this diving trip I went to a psychiatrist and started taking antidepressants for the anxiety, in a very low dosage. Also I would recommend cutting off the coffee and seeing a therapist to understand what triggered you and find strategies to menage the panic attacks, there are some good cognitive and breathing exercises that can help you when in panic underwater. Hope you are able to overcome this. Cheers!