I just found that several newbies have themselves as their referral. I think that this is some kind of bug in the referral system. I don't know how to put it in words clearly.
So here is an example -

As you can see in the above image the newbie is having 1 referral.

If you check whom he referred, it is the user himself. Here the referrer and referred are the same.
I believe that referrals are not being marked under the original referrer.