What Is The Treatment For Shaking Teeth?

I finished my Invisalign treatment about 2 months ago. Happy with the really nice results, almost perfect as can be. Since then I have had the Hawley (traditional acrylic +wire) retainer, which I wear at night.

Pretty ok with them, although I've noticed that around the tooth that was the key part of my orthodontic treatment there is some movement during the day. (lower incisor, I have an odd number of teeth between my lower canines - 3 teeth instead of 4, due to an extraction of left central incisor). When I wake up in the morning, that tooth/lower teeth are straighter than when I go the end of the day without them ....very slightly, but I can see it.

Now I found that that tooth I am talking about (lower right central incisor)..ACTUALLY MOVES a tiny bit when my two fingers rock it. It is wiggly. Not to the extent like a juvenile's loose tooth, but when I look closely in the mirror, I can see it. It's not loose like I am afraid it would fall or come off if I bit into an apple, of course not....but still, I seems loose.....? The other two teeth located laterally, also move slightly when pressed by fingers, but even less.

I am really scared. I know that after Orthodontic treatment, the periodontic ligaments under the tooth are not fully solidified in place...but I dunno...scares the hell out of me that something is really wrong. I am seeing my Ortho in 2 weeks, hope I dont have any serious issue.