Ok after playing through some other games I noticed I was having the same issue in games made with Unity. After doing some digging I figured out the issue, theres something wrong with the driver I have for controllers, even though I'm not using one, thats causing a constant up input (but only on games made in unity for some reason). Disabling this driver fixed things though, so I wanted to come back and change my feedback.
Fantastic work. The effects youre using are really well done. The combat was a little tricky, but I enjoyed it nonetheless. Good job!