I see. I just asked because you explicitly mentioned steem dollar and if you power up you are only payed in steem power.
With upvotes the problem is that you need upvotes from the right person. If I upvote your you get a 0.01 steem which will be rounded down to 0.00 at the end of the seven day period.
Steem is quite frustrating for new users. And I have the suspicion that the recent spike in the value of steem, when steem jumped form $2 to $8 has something to do with it.
If I understood the calculations correctly it could be that the new higher value steem makes payout less likely.