I was always told that if you hit your limit and THEN you get a jackpot or you get a challenge done, you get your credits. If you get it right before capping out, then you don’t get the full thing.
Sorry, I don’t know from first hand experience but I have heard you get Challenge credits even if you hit the limit. Like I said though I am not 100% sure. You could play it safe and wait until tommorrow to get the weekly done if that is an option for you.