Losing concept of time ?

My dad has been diagnosed with seronegative autoimmune encephalitis. He spent 4 weeks in ICU. He was on corticosteroids etc. then IVIg but it started affecting his kidneys so they stopped after 5 days. Then they put him on Kepra but there was a case of negligence lodged against his psychiatrist when she kind of over drugged him so they quickly got him discharged out of hospital before they finished treating him.

anyways while he’s back home and he says he feels confused and he is losing “trillions of hours”, he says he is “behind time” and some times minutes feel like hours. He also said he’s afraid to sleep because he feels like he might not wake up. He says he keeps getting lost [in time] if he’s left alone. Has anyone experienced this?