Is this normal in cold weather?

Yesterday, air was 47F and water 53F. I put on my 5mm, ski gloves, a neoprene hat and my closed-to bindings and went out for a ride.

However, I noticed immediately that I was running out of breath constantly, and I barely had the strength to hold the handle. I wasn't cold anywhere (I did a dock start).

I should be in peak shape, as my season started like 5 months ago, but I felt like I was in worse shape than if this were my first ride of the season. Another friend of mine exprienced the same thing last week.

Could this be related to breathing the cold air or anything else with the cold?