Recently I felt my palate has gotten a bit more wide so I have started pushing with the sides of my tongue (still not able to lay it flat without too much friction from the teeth) but it is significantly better now, by pushing at the sides I can notice a lot more work than before and the last couple of days I have this popping sound when I open my mouth and sometimes my jaw gets stuck, is this a sign that perhaps my bones are moving forward? am I doing something wrong? should I keep on mewing hard despite the TMJ discomfort?
On one side or both sides? If on one, you may be mewing in a way that enhances the existing asymmetrical development. You would not necessarily be regressing, but the better developed side would be developing even further, straining the condyles.. You could try shifting the direction of your bite & tongue until you find a combination that eases the symptoms.
An alternative explanation is that since the mandibular joint models itself according to the needs of the occlusion, it could be a simple matter of unfinished readjusting for the maxillary changes that have taken place. In this case the cure would be time.