The number of likes/dislikes in YouTube Analytics may be different than what you see on the watch page under the video. Our team is working to fix this. Please refer to the counts on the watch page under the video for the most accurate count. More info: https://goo.gl/Kb6j47
That's odd, our Creator Support team can dive into this further with you, contact them here: https://goo.gl/BxLi8H . Hope this gets resolved!