After Clark comes back, he seems okay, but in private he is a wreck dealing with the trauma if having died, come back to life, and then having to claw his way out of his own grave. Bruce is dealing with his tremendous guilt over how much he misjudged Clark and then hurt him.
It's when they run into each other in either Gotham or Metropolis that Bruce notices how bad Clark looks. Bruce confronts Clark which leads to a heated argument between them. The argument looks like its heading for another brawl, but then Bruce just looks really tired and worn and tells Clark how sorry he is for what he did to the Kryptonian and also that he knows Clark isn't alright. The understanding in Bruce's eyes is what finally gets Clark to let his veneer crumble. Things escalate after that. Afterwards, they both have nightmares about what they've been through, what's eating at them. Only now they won't have to deal with it alone.
Bruce/Clark: They Help Each Other with their Guilt and PTSD
It's when they run into each other in either Gotham or Metropolis that Bruce notices how bad Clark looks. Bruce confronts Clark which leads to a heated argument between them. The argument looks like its heading for another brawl, but then Bruce just looks really tired and worn and tells Clark how sorry he is for what he did to the Kryptonian and also that he knows Clark isn't alright. The understanding in Bruce's eyes is what finally gets Clark to let his veneer crumble. Things escalate after that. Afterwards, they both have nightmares about what they've been through, what's eating at them. Only now they won't have to deal with it alone.