You are wearing an Essix retainer, this is not the normal retainer,
such as a Hawley retainer, I never give essix retainers for "long" term
use.  they cover the occlusion and are only used for esthetic reasons
and timing issues, (at least in my practice)  I suggest getting a
different retainer made, most regaular retains your orthodonticst can
adjust your occlusion with, especially the front teeth.
invisalgn will cost a ton for you to do, and it's not worth it for the
money if you already went through braces and need only minor changing.
I would bring up your questions during your next retainer check appoitment.

Dr. Braces