Well... at the risk of suggesting the obvious... perhaps this is something you might delve into with a skilled mental health therapist. (Perhaps you're already seeing someone?) Of course, there's certainly nothing wrong with being asexual if that's the way you feel & you're comfortable with it. It's the uncertainty you seen to have, plus the apparent link to the trauma you experienced that may be of concern.

I do recall reading a reply to another post related to the topic of asexuality, written by a PC member who is knowledgeable on the subject. The replier wrote that it is common for asexual individuals to wonder about sex. Apparently it's not unusual for asexual persons to watch porn in an effort to gain some insight into the whole realm of sexuality. So perhaps what you're doing might, from that vantage point, be seen simply as your way of approaching or developing an understanding of sexuality? Clearly I don't know. I'm just guessing here.