Near death experience- how do I get over it?

Hi there! So me and my family are on vacation in obx, and I went to go into the water. Long story short, I can’t swim and I got caught in a riptide, EMS and lifeguards were there, whole thing. I genuinely think I could have died had I not had this little bodyboard. Anyway, it’s about 8 hours after getting out, and I am still terrified. I can’t get my heart rate down, I’m having trouble breathing, it’s just awful. Every time I stop distracting myself the fear comes back. How do I get myself over it? I have a really severe anxiety disorder and I think that’s what’s making this so bad. So yeah, any advice on how to calm down would be awesome