Hello,
Sounds like a classic case of hydrophobia to me (similar to claustrophobia) The solution is so simple it's not funny. It does take a special instructor who's familar with it and knows how to deal with it but you can make a full recovery and actually enjoy diving.
As stated above diving underwater is very alien to the human body but it can be trained to overcome this obsticle. What is recomended is to start in the shallow end of the pool and slowly adjust to that then add one step at a time. I.e. get used to breathing underwater, then actually put the bc on and get use to the feel of it. Also the equipment makes a world of difference, as if your using stuff that you don't feel confortable or uneasy with you'll have a harder/longer time adjusting to it. Some people are more suited towards certain types of dives than others, i.e. colder water, limited visibility, overhead, etc.. There is NO one correct way of doing things.
As for getting 'psyched' I suspect that there's some reservations (either on the part of the people your diving with, the location, the equipment, time of year, etc) about doing this particular issue. I.e. you can take a person who has alot of stress level at dive spot A and put them in dive spot B and you'll never see that stress level, why? the situation makes all the difference in the world. Why is this important? Because there's a specific type of diving that best suited to you and you need to figure out what type that is. Think about what enviroments you want to be in, what situations you would be more at ease with and once you have that work towards it.
By no means should you ever dive when you have a bad feeling about it. This is where pre-dive visualization comes in. Start by thinking of what you want to dive (situation/enviroment/etc.) then plan everything (here control is critical as you'll feel more at ease and 'in control' of the situation) plan the dive then dive your plan. Before the dive think about the beauty of what it must feel like to actually have this 'dream dive', get into a state of relaxation and just mentaly imagine diving. Once you get into the water you'll have a possitive attitude and your body will be eagerly looking forward to filling the mental images you just gave yourself.
Durring the dive when you feel yourself becoming stressed just imagine that mental image you gave yourself back on the surface and think how calm you felt then and tell yourself you are calm and in control. In fact YOU are in control at ALL times, you just need to constantly reassure yourself of this. I find that stressed divers tend to look at their mistakes and are so self conscious that they forget the critical issue at hand, have fun and enjoy yourself. In situations like this it's imperative to distract the attention to the surroundings, like that fish, that rock formation, that intricate pattern of schooling fish, that goby, or ANYTHING to distract the self imposed pressure of performing (in a pool this is very hard to do as there's hardly nothing to look at.
hydrophobia/claustrophobia isn't something that you "just get over" it's a conditional responce to a specific type of conditions. Find out what the key is that makes you uneasy and work to remove that factor. Just remember your not alone as many, MANY, divers have encountered this situation and have overcome it, so can you.
I hope this helps.
Ed
