Feedback Admob requests dropped to zero

I just released my first android app on Play Store.
I had some positive climb this week in requests, as you can see very low impressions.
I'd say about 10+ users in different countries.
A couple of questions, please share your experience:

Does it look odd to anyone to just drop to zero like this?
How accurate is admob in these stats; and is there a big delay or something?

Tab "Last 7 days vs previous 7 days"

 

It's kind of weird that if I choose the tab for "today so far", it does in fact show Requests and impressions but no eCPM