I got a situation, can any steem expert help me on this?

Today when I checked the steemd, I was shocked to see that my downvote power is below 70%. I has been a long long time since I have not used that feature anymore. I was also worried because I thought some third party steem-app might have been misusing my accounts voting power. I checked 3 days of mine transaction on steemd and still couldn't find any downvote transaction there.

Then I thought it might be some kind of intentional bug on steemd and checked on steemnow but there also my downvote power is below 70%, here's the screenshot from the steemnow as well.

Now I am very much worried regarding my account and it's security. I will change my key very soon and wait for few days to see what will happen.

But my concern and question is how the heck my downvoting power decreased when I have never touched that downvote button.
And if in case some third party apps that I have previously granted voting permission have misused it, then why those transactions aren't appearing on steemd?

I regularly check my transactions on steemd and my downvoting power was fine till yesterday or the day before yesterday.

Does somebody else also experiencing same kind of situation here? Can somebody answer me and on this and clear my doubts??