Is it normal to be a Asexual?

Meh, I would have to disagree. I don't view intelligence and sex drive to be on the area. As men are more sexually driven than women, this would suggest that more women would be the smartest, and so on, when it's shown that the smartest of people tend to be males that are not asexual.

I don't think sex makes anyone less intelligent than the other. Sure there may different priorities, but I doubt not having those priorities makes someone smarter than those that do, they just have more time to focus their attention on other things. There are more ways for positive feelings than sex, and if they are not occupied on sex as one priority, a less productive priority might fill that space, such as media or video games, etc. If anything, it is more of a downfall to be asexual, as you do not possess that nature need to reproduce, which without it humanity wouldn't of existed this long, or there will be very few humans to come to this level of progression we have attained now.

Also, being asexual does not mean you do not love, it just means you are not sexually active, so looking for the 'right one' would still be something Asexuals would do.

So basically, sure they may have different priorities, but that does not mean they are smarter, if you get what I mean.

I don't believe it is a downfall at all. Without it, I doubt we would of ever come this far, as explained above.