I second fish's post. Even if you decide you aren't asexual, you might find AVEN helpful to your situation.

What I noticed, and this might just be your wording, is "I don't think I've ever been sexually attracted to anyone to the point that I feel the need to have sex". Do you not experience sexual attraction at all, or do you experience it and just not really have the motivation to act on it? The former is asexuality, the latter is sex drive. I would also go so far as to ask whether what you are feeling is in fact sexual attraction or whether you are merely attracted to the look of a person without that having a sexual component- we call that aesthetic attraction.

If you are concerned and think your sex drive is an issue then there's nothing to stop you from investigating that with a doctor independently of your sexual orientation.