The Final Nail (слэш)

It was just supposed to be a harmless prank. But now Clint was in the hospital and everyone was furious at Tony, and Tony was convinced he was going to end up alone again.
Prompt A (paraphrased): Tony and Bucky get into a fight; Bucky says he's done and storms out, so angry he doesn't hear Tony pleading with him to come back. Bucky returns later, now calm, to find Tony having a panic attack.
combined with
Prompt B (paraphrased): the team gets in a fight and everyone is giving Tony the silent treatment and/or snapping at him. Tony's anxiety takes over. That night Bucky finds Tony terrified to be alone and convinced that the team hates him now.