I'm seeing double red dots

I get a fuzzy, overlapping second dot when I look through my only red dot. 

I watched a YouTube video & it said if you look through the red dot while rotating it & the second dot doesn't rotate with the scope it's due to your vision, most likely astigmatism.

They also suggested looking through a red dot through the camera on your phone. If the dot distortion disappears then it's likely your vision. 

I'll see if I can find the video.