Completely Disgraceful

With an upcoming debut at the pumpkin man triathlon I decided it was time for an open water swim. Lee's pond, S. Berwick ME. was the decided site. After a brief 4 mile bike ride there with two friends we donned the gear made it 100 yards into the water until I became completely gripped with panic.
It should be noted that I am what most would consider a strong swimmer and most of my favorite leisure activities take place on water. I have been swimming multiple times per week for the past two years. None of this made a lick of difference.
Staring face down into a pond the color of Guinnes, my chest going tight and heart racing. I wanted to do something but I couldn't place it. Looking back at night I figured it out, I wanted to sob. I was in no danger what so ever, there is absolutely nothing in this water with any capability to harm me.
It wasn't a fear of some leviathan, being eaten wasn't even a thought. It was the water itself. This absurd idea that I would be drawn down to the center of the earth and covered by a layer of liquid with out end. Black, soundless and completely alone. I am afraid of the dark. I am afraid of being alone. As an adult we are rarely faced with admitting shortcomings like this. In the night you can sing to yourself, talk to yourself, be your own company. Here it felt like I had nothing. Putting my face under for each new stroke was agony. I rolled onto my back, stroking slowly watching the sky. Eventually I over came it, swimming freestyle eyes tightly closed. Only opening them to confirm I was headed to the island and then back to shore where my bike was waiting.
I am disgusted with myself. I hate being afraid. It destroys dignity and ability. My friend Amy was good enough to take it easy with me while I pulled it back together. We both completed the swim but it was dreadfully slow and fatiguing. I rode home like the devil was chasing me. Flagellating myself the entire way.

Post Script:
I have since pedaled to the ocean where I did a half mile swim. I felt much more at ease.