And I still maintain historical periods are not invented in the present by historians. Their names are, and the transitions between periods are obviously wide and blurred, but movement between periods in socio-historic terms is attested to by people living at the time too, eg the Petrarch example earlier and, I'm sure, many others.
People will always recognize change, especially when it's unwelcome change. No doubt people in the sixteenth century were complaining about all of the new innovations in art, science, literature, customs, and such, just as folks in the 1950s complained about the baneful influences of television, comic books, and rock and roll. Indeed, it would be far more surprising if you found people complaining about the fact that nothing
The danger is that you will rely on contemporaneous reports of change to justify your preconceived notions about when and why change took place. For instance, if you believe that the Renaissance ended in the 1490s, then you can look at reports of change from the 1490s to confirm your initial premise, while ignoring or discounting reports from other decades that also indicate that changes were taking place.
As it is, nobody in the 1490s said that they were sorry (or relieved) to see the end of the Renaissance, because that term simply wasn't used until much later. People may have recognized changes around them, but they also would have recognized continuities. Art and architecture, for instance, didn't cease on the day that Charles VIII invaded Italy, only to be reinvented as something entirely new the next day. There was no revolution, only an evolution.