I had a friend who was in NY a few weeks after. He said the sight was horrendous but what he would remember most vividly was the smell.
I lived 30 miles west of Manhattan and the smell lasted for about two weeks even out there. You could see the smoke from the rubble pile from the hill above my house.
When the first plane hit I had a feeling we were under attack. Having worked at Ellis Island a few years before, I knew nobody could have “accidentally” crashed a plane into World Trade on a clear day.