Lol, I never noticed that my votes made a user's upvote go down. I am pretty sure that has to do with the market price of SteemIt.

To generate income, I suggest you join contests and games that pay out liquid Steem or SBD or @steembasicincome shares. Also, try to comment on as many posts on which the author has set a bounty as possible.
You can find all those @steem-bounty posts here: https://steem-bounty.com/