I think they had an argument before .Im sure that Ohm was stressed , tired , everyone can be stressed or tired and they won't think about yourself or something disturbed him his hands were shaking so nannon looked worried, and because he was upset that ohm won't think about his health.
Im sure that ohm is the type of person who no matter how sick he is, always finishes the job, ohm look like he was sick, even his hands were shaking so nannon looked worried, and because he was upset that ohm won't think about his health. Maybe that's why he was angry just tired as he should think about yourself because its important not job