The number of reviews that you get depends on when you did your lessons and what you get right, in a way.
Did you read in the WK FAQ about the SRS system and the time spacing? If not, I’d suggest that it’s a good thing to read up on to better understand how WK does things. ^^
With regards to your question:
When you hit the “reviews” bubble on your dashboard, it first takes you to the review summary screen. Is there a chance that you mistook the number that you saw there as your upcoming review number?
Otherwise the only thing that I can think of is that you were on a tab that had not been refreshed yet, which can mean that you see an old number on the dashboard.
If it happens more than once, you can always email the WK staff at email@example.com or you can come back here and we can try to tag a mod to look into it.
But I personally say a small oversight like that happens sometimes, and it’s unlikely that anything is actually wrong. Keep at it, and I’m sure it’ll be fine. ^^