Father has declined after hospital stay - is this normal?

My 93-year old father (recently diagnosed with dementia and living independently, with my mother), fell in the apartment 12 days ago (in fact, he also brought my mother down, as he was trying to stop her walking out of the room but that's another story - she was OK). Ambulance was called as he couldn't get up and he was taken to hospital. Nothing broken - he had a scan and a full check-up and we assumed he'd be sent home almost straight away but he's been in there for 12 days. Part of the issue I think has been lack of carers/support for him once he was discharged, so this has caused a delay. He is in fact coming out today and hopefully with a care package (although this hasn't actually been confirmed). My concern is, that while he was in hospital, he deteriorated. For example, he has never done this before, but he wet the bed and soiled the bed, on 2 separate occasions and soiled himself during the day, while he was sitting in the chair by the side of the bed. Has anyone else had experience of this? Is it part of dementia or could it be the effects of being in hospital (I am hoping it's the latter and now that he's out, he will stop this, as it will be very difficult for my mother to cope with).