I'm so sorry for your loss - I went through the same thing and had the ERPC on 7th March.
I was a wreck - I couldn't think what to pack. I wore jeans & a hoodie - I took PJs and wash bag with me - they recommend that in case you have to stay.
I wouldn't have had the attention span for a book - I played games on my phone as a distraction and wished I'd brought my charger!
I didn't need pads - I bought loads, brought 2 with me, they gave me one in recovery, it was completely clean, I wore it home - I didn't even need to change it.
They got me into a gown when I arrived about 7am - op was scheduled for 9.15 - but it was delayed by a bit because I absentmindedly popped a piece of chewing gum in my mouth on the way into the hospital (nil by mouth)!!! I was furious with myself - but I was scared and my mouth was dry - it was a reflex reaction...
I was out of theatre for about 11 and I was in a lot of pain and they gave me morphine - so they kept me in recovery for a bit longer to make sure I didn't have a reaction.
I had tea and toast when I went back to the ward - I had to wait more for the surgeon to debrief me, various nurses with leaflets, the pharmacist with painkillers for home. I asked about 2pm if I could go home, rang my dad and left - I told them he was outside... I just wanted air!
That night I could have done anything - I was exhilarated (morphine). The following day was BAD - I woke up crying, pain, devastation... I was a mess. Don't expect too much of yourself - you might be fine, but don't beat yourself up for feeling bad on top of everything else.
Be kind to yourself - I'll be thinking about you tomorrow. Don't hesitate to PM me or message back on this thread if you have questions or need anything 