Front Teeth Hitting and Bite off After Invisalign. Lower Jaw Feels Like It Has Moved Forward During Invisalign Process. Advice?

What you describe is insuuficient posterior support or overly retracted anterior.  This can lead to serious problems with the Temporomandibular joints (TMJ, TMD) , headaches, migraines, jaw pain, sinus pain, earaches and/or excessive wear of the antwrior teeth.

Make sure your bite is corrected before more serious problems develop.  

Invisalign is best done by dentists who have a thorough understanding of TM Joint mechanics and CranioMandibular muscle physiology.

What you're experiencing is actually a good thing.  It means that your lower jaw was held back because of the shape of your upper arch.  With the upper arch expanded now, the lower jaw assumes a more forward position because it's more comfortable for the muscles. Now you need to have more trays made to move the teeth to support this more forward jaw position. It may take a little time for your brain to accept this new bite, but in the long run, you'll be much better off.