If you go to your profile under the "Statistics" tab, you'll see your daily posting average. Right now it looks like you're at about 47 posts per day. I believe you're considered a super poster at 2 posts or more per day. You've just joined, so this average will go down as the newness of the site wears off and you post less. Other than waiting to see if this happens, I don't know any way that the super poster title can be removed. Have you tried PMing DocJohn or a Moderator?