Tim is gonna be up all night.
That's the first thing you noticed; he had a specific pattern of actions hinting at it. Saying he'll be in bed with you soon before leaving you alone for an hour. Calling Bruce. Pulling out the godforsaken pinboard and red string. Yet another case he's gonna lose sleep over.
So, being the lovely partner you are, you made him coffee. Well, it's the opposite of coffee, probably. You made him chamomile tea.
"Wait, this isn't coffee," He murmurs after drinking most of the mug. Being the great detective he is, it's hard to believe he didn't figure out sooner.
But now he feels sleepy. Not energetic, like he should be..
"Did you drug me? Oh my god, you totally drugged me." You did not drug him. He yawns.
Tim will not be up all night.