I don't see it that way. To paraphrase Coach Stevens, "It was just one loss."
The Celtics have often been guilty of underestimating opponents, and that is what I believe happened. However it does show a chink in the Heat's armor...they are not willing to put maximum effort into every game (whether by preparation or execution does not matter) and that shows a little sense of entitlement.
It was a good win for the Celtics (although again, Coach Steven's said "It was just one win.") It showed that the Celtics are starting to play as a team, to trust each other's game, and to be willing to put in the effort and not give up until the final buzzer. Since we are now a younger team, I am not going to say "despite being the second road game in back to back games"....whoops!

Good Signs. And it was the kind of win we fans needed to give us hope and quell the tanking talk.
On a personal note, I have not stopped grinning since last night, and my jaw and cheeks are really hurting!