Thor has no idea where the impulse comes from. He hasn't really talked to any of the Avengers since they left to kill Thanos, and none of them had particularly gone out of their way to contact him. It didn't particularly bother him; in fact, very few things did these days under the guiding hand of alcohol.
It was perhaps that very hand that pushed him to pull up Tony's name on his list of contacts instead of something more sensible, like powering the phone off entirely.
"Stark, Stark," Thor nearly shouts into the receiver. "What are you -- What are you doing?"
It's 2:05 AM on the US east coast. It's breakfast in Norway, where Asgard (well,
New Asgard is now). Thor has been up for 22 hours now, fueled only by a copious amount of alcohol, half-burnt waffles prepared by Korg, and the desire to unlock the final trophy in his video game of choice.