I’ve just done some research. It may be aqua phobia or hydrophobia - Thalassophobia is the fear of large bodies of water. Hydrophobia is the fear of being in a body of water no matter how small. Not sure if this helps but this is what I found

All the fancy "scientific" names are just saying stuff in another language Homo=man Sapien=wise Terminology is very useful, so if you're looking for solutions, or trying to communicate your struggles, then a specialized term might be useful, But there's always nuance, it could be helpful to explore ways of communicating and describing your fears Elaborately and succinctly I do fear XYZ I don't fear ABC You can also think of ways to conquer your fears What is definitely doable Holding your breath for 2 seconds inside your house, nowhere near water Holding breath and plugging nose Wearing a snorkel and mask in your house no water involved There's probably much better and more specific procedures and lists You could look in medical and psychology fields But you might find better help for this specific struggle in aquatics fields Scuba, boating, military training, live guard training There's probably hundreds of very effective methods used every day to help people in these industries overcome fears themselves and help students and colleagues overcome You could probably get better results with helpers, both experienced and inexperienced Having someone there can help keep things in perspective, Help us laugh at the monsters in our minds Someone to hold our hand, Someone to trust, let go of control to Eg you can have a friend tell you how long to hold breath, Also finding ways to laugh at fear can help If you can find ways to laugh during exercises Maybe put in your favorite funny movies, try to hold breath right before funny bitts, and try to laugh Hopefully that's helpful and not annoying good luck