How old is mum?
I am 64 and was 63 when I had the surgery.
My surgeon said “ the biological processes take a little longer” when I said something like
“ I’m not the spring chicken I once was”.
It’s a big surgery and everyone heals differently but it is true the older you get ( all things being equal) the more surgery knocks you around.
The important things are to rest, take the pain meds, stay hydrated , eat healthy things like pots of fresh fruit and veg and lean protein and try a bit of gentle walking to get things moving.
And follow Drs orders.
I am not a patient person so it was hard for me but in the end I recovered and the pain and discomfort receded from my memory .