Last night he was out with friends, went back to a party and text to say he was gonna crash there. I’ve no idea where he is or who he’s with.
You say you're happy with him having solo nights out, which is well & good as it would be odd to be otherwise - even in a committed cohabiting relationship.
But are you really ...?
Because you DO know where he is & who he's with.
He's with friends, at a party, & crashing at the party friend's house.
Why would you need more info than that - or more immediate info?
Surely when you next see him that info will come up naturally? -
"yeah, we went to Steve's to watch the XYZ/carry on drinking/playstation/whatever - you should have seen the state of Alan! - I lost a drinking game, lots of fun, we found Ben fast asleep clutching the base of the bog ..."
ie the standard party postmortem beloved of pals everywhere?
So the real question is - why did you need to know in real time? To check up on him? Vet what other women are around who else is there?
If you'd posted that your b/f was upset (enough to start a forum post for advice!) about not being given chapter & verse about your exact whereabouts & companions while you were still enjoying your night out, I'd be telling you to watch the red flags & start being very alert for other signs of controlling behaviour.