So I just reading some posts, commenting, and upvoting. And all of sudden, I mistakenly clicked on the downvote button for one of the recent posts by 
My Reaction
As soon as I saw the pop-up asking me to confirm my downvote, I got so scared that I just backed off my hands from the laptop and sat still thinking what have I done. It took me 1-2 minutes to realize that I haven't done anything wrong, it's just a confirmation window and I have not yet downvoted the content.
OMG! It was an unacceptable feeling altogether. It felt like I've done a blunder. Over the past few days, we have been reading so much about this downvoting thing, how it is negatively impacting the platform, rules governing downvoting, some people agreeing, others disagreeing. I think all of that took a toll on me. It suddenly gave me a feeling that I will be thrown out of the platform, haha.
How would have I undone my action
But I know, even if I would have done this by mistake, I would write an apology to the owner of the post and they would understand that it was a genuine mistake.
Comparing to other Social Media
We have seen on the social media platforms like Facebook that the dislike button is next to the like button or it's the same icon (like in Instagram). But given platforms like hive and proof of brain are completely different and a downvote here means taking away the rewards of the owner, we should make some changes here.
My Suggestion
So I just want to make a small proposal here. Instead of having the downvote button just next to the upvote button, we should have it separately at a place on the screen where there are no other buttons so that one doesn't end up accidentally downvoting a post. This way someone would reach out to the button when they really intend to do so. 
Mockup
I am a business analyst by profession and I work on enhancing the user experience for my product. I think this change will be a good experience for the users and would avoid unnecessary downvotes.
Hoping this helps the community as a whole. Have a good day!