Cinema Geekly wrote:
Spock used highly sensitive chronomatric sensors aboard the Jellyfish just as he emerged from the black hole and realized that there was a slight difference in the readings informing him that he was not in his Universe.
He didn't know exactly what, where, when he was until he met Kirk in the ice cave.
That's why he seems so cool with Vulcan being gone when he is talking to Kirk because he knows his place is safe and sound. In fact I would assume Spock is more upset that Romulus PRIME is gone since in the Countdown comics it is revealed that is where he now lives.
He wasn't "cool" with Vulcan's destruction at all. Kirk was crying his eyes out at the end of the mind meld - to which Spock said, "emotional transferrence is an effect of the mind meld." Those were Spock's tears. He also choked up a little when telling Kirk "I just lost my planet. I can tell you, I am emotionally compromised."
He'd be a total dick if he just went, "Meh, not my history."