Just skimmed through it. I'm sorry, but biased doesn't begin to describe it. Yeesh.
But yes, given the story as I understand it, it's heroic even if going agains the decision of his aunt. Aunt May telling him not to is no different from the many times a hero hears, "Save yourself! I'm not worth it!" Usually, we expect the hero to ignore the plea and risk their life and run into the burning building anyway or whatever.