How Nice can you be?

Can I classify myself as a nice guy? Yesterday at work a senior college dropped her key and I was close by, so I bent down and picked it for her and she sounded impressed (like it was a big deal) and called me a gentle man. Later in the day, another college sought for a person to do her a favour (don’t ask me what the favour is), and I was quickly recommended by the earlier lady and of course, with the reason that I am nice and wouldn’t decline doing the favour. I did not disappoint her either. This was just yesterday. There are numerous examples in the past of me being nice to people (male and female alike) without even me giving my action a second thought. But now I have come to realise that I should give it a second thought.