I respect that you gave it a shot, and understand that especially when working in sales, being and feeling clean can be pretty important.
I'll second the suggestions regarding giving yourself some cool-down time once you get to work. I keep a small fan on my desk and let that blow on me for about 10-15 minutes before I wipe myself down with a washcloth in the bathroom. Afterwards, I feel pretty refreshed and dry.
At any rate, I encourage you to keep an eye on the morning temps and give it a try again when the weather cools down some more.
Scott