Referral credit is only going to be put in your account if someone gave you their number who is an active customer. Without number from friend or family member who is a customer you won't get referral credit.
Did you use someones number when registering?
I also registered with a referral, it took a couple days to pop up on my account self serve. I would wait it out! It should be applied to your new payment and seen as a "account credit" on your public mobile account.
I've made a couple referrals and got the credit the next day for each.. :/
The referral code provided by the referrer is entered at the time of activation, and as such the referrer gets the $1 almost immediately. The referee gets it within a couple of days.