High surf, cloudy water stepped on something like a snake

I'll be definitive. It was an eel, very unlikely a sea snake. This is the time of year that when we are out very very early with our dogs, either one of them jumps vertically into the air looking silly, or one of us steps on one and I scream like the girl that I am!

We do, very ocasionally year around, see black and yellow sea snakes, but even in the dark they are readily identificable.

Neither will hurt you and if you didn't scream like a girl, you did great!