Phonecall
Jack toys with his mobile for awhile, thumb moving to and away from the number over and over. The TARDIS's coral ceiling overhead in his bedroom isn't unpleasant to look at, but you can only stare at a ceiling for so long. It may be too soon to make a call, no idea how long you're supposed to wait with these things, but he's missing the Captain and feeling impulsive, and a phonecall seems like the most reasonable option to get back in touch. No awkwardness of keeping their hands to themselves, that's important. Hard to start over and be friends if you're trying to resist the urge to pounce.

Well, what the hell, worth a call. He hits the button to call the Captain and waits to see if it's picked up.