You're not welcome

So I'm headed into a Wawa on the way to work today, and as I'm approaching the door I see a guy coming toward the door on his way out as fast as I'm heading in. He beats me to the door by a fraction of a second, at which point I notice that in his right hand he's holding both a newspaper and a cup of coffee, and he's got his left hand extended to push the door open. Not quite sure what to do, I just stop and let him through.

As the door is swinging open and he is about to pass by me, we have a brief conversation. It went like this:

Me: "Thanks."
Guy: "Nope."

It was odd. He did not say it with venom or with bitterness, or with a great deal of vitality. He said it clearly, a little crisply, like someone smoothly pulling a grape off of a bunch and popping it in their mouth.

I felt bad. After re-running the very short scene in my mind a few times, I came to the conclusion that he believed it must have been very clear to me that his hands were moderately full, and that I was an ass to stand there while he awkwardly held a cup of coffee and another object in one hand. He must have thought it odd that I seemed to think that he had opened the door as a gesture of politeness to me. I couldn't help but think that I had just reinforced his belief that people are selfish and inconsiderate.

And then I was bothered that I was bothered. I wanted to tell someone else what had happened, and I was embarrassed at the thought of doing that. My intention had not been bad, but... I had been in a hurry. He had been in a hurry.

Would it have been better if I had said nothing?