I asked this guy if he thinks I am attractive and all he said back to me was “I have seen better.”  Does this mean he thinks I am attractive?

It definitely means he’s an asshole.

After someone unquestionably reveals their “asshole-ishness” to me, what they think of me is of microscopically little importance.

Hopefully you will adopt the same criteria for friends and romantic/sexual partners. That criteria is don’t insult people.

He could have just said, “I’m sorry. I’m just not attracted to you. Someone else might be very attracted to you, however. Best of luck.”

The fact that he wouldn’t even consider your feelings is a warning about the kind of person he is. Go find a guy who (1) finds you attractive and (2) is considerate of your feelings. If you desire it, bask in his appreciative attention (verbal and non-verbal).

All the best.