Is it normal for my fingers to feel numb after carpal tunnel surgery?

Yes. Give it time to heal. This can improve with time.
Maybe. Carpal tunnel release is done to relieve pressure on the median nerve. If the pressure has been longstanding or severe, resolution of numbness may take some time and may never completely resolve. In such cases, ctr will prevent any further damage to the nerve.
Possibly. If numbness was constant rather than intermittent before surgery it may rake longer to fo away after, or may not go away. Surgery still kept it from getting worse. Constant preop numbness implies increased risk of postop permanent numbness.