I recieved Pearl's in the challenge>reward section, for about two days. The description said it was 50 a day for the value pack.

Was it a bug that I got them?

OR

Is it a bug that I'm not getting more, despite having the value pack?

That was most likely due to the fact that buff was still active for the entire day on the 22nd in NA meaning it did not go away at server reset where we get our attendance rewards and loyalty points. As far as I know it was unintentional and I don't believe there's anyway to buy a premium VP in the Pearl Shop just a standard one so its not a bug that you're not recieving any more daily pearls. 

Hope this clears up some discrepancies.