Possibly... Even though I have 4 years of NI contributions, I have never had a full time job in the UK, only summer work or temping agency part time jobs. If I was making sufficient contributions from those I'd be very surprised seeing how irregular the hours were... Maybe if you're in full-time education, the contribution thresholds are much lower...
I'm so in shock about lucking out with class 2 repayments, I'm almost waiting for the letter/phonecall to say they made a mistake. I won't really be able to sleep easy until those Direct Debit repayments start early next month...