Does anyone else have this issue? The last time we anchored, our P323 sailed back all night long. there was no sensation of moving when we were in the cabin until we looked out the windows...then, wow!

We were zipping back and forth at a pretty good clip.
we had at least 7:1 SCOPE, and the wind it was blowing 12 to 15 knots all night. Maybe this is normal?
We are thinking of making our own "anchor riding sail"...
Any comments?
Chet