Invisalign over-correctors? They made my teeth crooked after they were straight, I got retainers while they were crooked?(photo)

I finished Invisalign and got a retainer. The over correctors at the end of treatment made my teeth crooked after they were straight. I guess the over correctors push the teeth further past being straight since they shift back. When I got retainer impressions, I asked my dentist why it makes sense to do it based on the crooked impressions. She said over time they shift back. How can they shift back if every night I am locking them in that position? It has been months and no sign of them moving.