The car dropped him off on the curb at 221 Baker Street. John dreaded facing Sherlock, but he couldn't think of anywhere else better to go, and falling facedown into bed was sounding more and more appealing by the second. He didn't think he could take anymore today. Unfortunately, fate wasn't feeling particularly kind.
"Crime in Progress. Please disturb." the note on the door read in Sherlock's spidery handwriting. Of course... Why on earth had he expected a peaceful evening?
He'd found Sherlock upstairs in their flat, seething with unspoken fury, a gun pointed at the same American who'd ordered Watson shot at Irene Addler's house. Apparently, the bastard wasn't content with trying to shoot detectives or their partners - no, he'd moved on to attacking old ladies. John hadn't felt particularly bad about leaving the man alone to face whatever wrath Sherlock felt like unleashing upon him when he escorted Mrs. Hudson downstairs to have a look at her injuries.
The loud thump of a man crashing into trash-bins from the upstairs window confirmed Sherlock was still in a bad mood. John suppressed the urge to smile when he noticed Sherlock retrieving the man and dragging him back up the stairs for another go.
After the police had collected the man (three drops in total later) and left, Sherlock had joined him in Mrs. Hudson's kitchen. He quickly dismissed John's attempt to assert his authority as a doctor and send Mrs. Hudson away for some rest.
"Mrs. Hudson leave Baker Street? England would fall!" He'd declared, putting an affectionate arm around their shaken land-lady. She'd accepted the gesture just as affectionately, leaning her head into Sherlock's hip. The scene made John smile in spite of himself.
Stop being so damned adorable, you difficult bastard.