How Long Does Collagen Take to Rebuild?

Hi! Ive had 2 fraxel restore treatments. My last session was a month ago and I've spaced them around six weeks apart so it's been around two and a half months total. Question: is there a "sweet spot" if you will on the collagen recovery process where my skin really kicks in with healing/rebuilding itself? I've just noticed it going from great looking to stressed looking and I'm wondering if underneath its trying to build up the collagen and in due time I will see my final results? Thanks!