I'm confused why this just happened. I dont have cancellation, so I used dispel as it said it had a reduced chance to get rid of the negative effect. The dispel worked and removed the spell I had on me, but then said my knowledge was reduced and I check my skill list to find it is now 1% in this spell?

If dispel can be used on ones self to accomplish the effect why would I be punished for doing so?

How is a player who doesnt have experience with a spell casting class to know what can or cannot be cast on one's self without catastrophic effect. In this case a permanent loss of practices?