Is it normal to crave pain relievers?

I'm 14, and no, I'm not sick, nor do I have any pain of any sort, but there's something in Alieve's or any pain reliever, that I crave day by day... I don't take them EVERY day, but when I take medication for allergies, or if I'm just getting water, I tend to grab a couple... its almost a reflex, or as if I NEED something in the pill... In the end, it doesn't feel like a terrible addiction... heck, I cud live without em... but is this normal, at all?? Any help, attempts, or opinions would be greatly appreciated. :) thx.