I was shoveling snow for about an hour, and felt fine while doing it. It didn t feel cold while doing it, but other people were shivering. Once I stepped inside, however, I felt very strange, and my perception of color became distorted. I began seeing strange light blue color everywhere. This went away after lying down, but I still felt light-headed. Does this sometimes happen? I am only 27, and used to exercise regularly, but have been mostly inactive the past few months.