So, the vote score you see is the combination of upvotes and downvotes.

You have two upvotes and three downvotes on your question, for a total of -1 score.  I've even screenshot the current vote counts:

[![enter image description here][1]][1]

If somewhere it says -2 on the screen for you, it's incorrect, and you may have a cached page view or something in your browser cache you have to clear out.

  [1]: https://i.sstatic.net/tFHQe.png