Flagging will make your payout go down... but that's probably not why your payout is going down... if you've been flagged you'll see 1-3 little dots in the upper right hand corner of your post that look like this:
Right now pending payout are going down because hardfork 19 is recalculating rewards over a 30 day period and this could continue for a few more weeks before payouts start to stabilize. (simplified answer) But we'll get there!
Also if the price of STEEM falls your pending payout will also drop. Or it will go up is the price rises.
You are so AWESOME for explaining that! Aww man, I thought I was getting on certain people's nerves 'all the time' -- ha ha.. Now, I can tell when I am and when it's finance related.