There are so many factors - the nature of the death itself, the wider circumstances (eg are now caring for an elderly bereaved parent or handling the funeral all by yourself), your job, your family, your own health and mental well-being outside the impact of the bereavement. I simply don’t think there is a one-size fits all answer, and any manager who can’t understand that seriously needs some training.
I took a week off after my dad died a very slow death from cancer. I was exceptionally fortunate, I suppose, that I was permitted time off before my dad died so in total it was almost two weeks.
I had the most amazing conversation with our Head of Department at the time, he was an absolute ball-breaker at work most of the time but he apparently had a much softer side and gave me the best advice about grief and bereavement I have ever had. I don’t think I’d have been able to function without that kindness and the understanding. He left me in no doubt that if being at work and “acting normal” wasn’t helping, I could take some additional time off. In fact being at work did help, as I had lots of close friends in my office who I understood I needed a bit of respite from the emotional intensity of supporting my mum in her bottomless pit of grief whilst wrangling my own misery (I was pregnant at the time, and rather anxious about that as well).
When my mum died though - that was different. It was very sudden, we were very close, and I was her only relative in the UK. Just all the practical stuff was immense - clearing out the fridge, putting out her bins, taking her laundry out of the washing machine, phoning everyone to let them know their friend had died, all the administration with the undertakers… I could have drowned in all the tears. But I couldn’t take time off work as I was in probation in a brand new job and I had little kids to look after too. I think I dealt with my mum’s death better in the long run than my dad’s, maybe because she didn’t suffer. Or maybe because I had to put myself back together, really fast, there just wasn’t any choice.
Simply the physical exhaustion of someone dying can be enough to need a few weeks to recover from - the late nights before they pass away often spent on uncomfortable hospital chairs, all the housework you’re behind on, then those sleepless nights and nightmares after the death. I felt like the image of my mum’s face in her last minutes was burned on the inside of my eyelids and every time I shut my eyes, there it was, in all the brutal detail my mind chose to recall.
It took me a year to empty and sell my mum’s house - I was really lucky she owned a home and I didn’t have to empty it instantly like you often do with rented or council housing.
Oh I don’t know really OP - if you need the time just take it. There will be time in future to make it up to your colleagues if you feel bad about it.