Lightheaded/Almost fainted at end of dive for 20 seconds - heart started pounding

[ScubaJill]

I had something similar once. I went after a Spotted Eagle Ray a little too quickly and afterwards it felt like I had been on a roller coaster. I was in about 15-20 feet of water. I tend to get a little vertigo and nauseated when moving my head too much in surge conditions, though.

Edited: What did the professionals tell you?

 

[Duke Dive Medicine]

During immersion the effect of gravity on the blood is essentially neutralized, so orthostatic hypotension would be very unlikely. To PVTAMPASCUBA: You said this happened twice. The first time it happened, were you changing depth as well? How quickly did it resolve the first time? A couple of other posters have suggested vertigo; did you have the feeling that the world was spinning, or did you feel as if you were about to faint? Do you recall any sinus issues during either of these dives?

Best regards,
DDM