All the above mentioned risks. I have had two CSs and no natural birth.
The first CS I could barely walk afterwards. I was utterly unprepared for the level of pain involved recovering, certainly the first few days. I cried trying to walk down the hospital corridor just to go to the loo, could just about push the handle to flush the loo. Everything done very very slowly and wincing all the time. It is massively uncomfortable to hold your baby, I could not pick him up myself, had to call a midwife every time I needed to pick him up (lots). I had to sleep propped up on my back for weeks which gave me awful backache. I had infections in the scar both times.
During my second labour the CS scar completley ruptured and I had a CS under general. DD went to NICU and I did not get out of recovery for 36 hours: I did not see her until 36 hours after she was born, other than a flimsy little photo of a baby with lots of electrodes stuck on her. I feel that I was not present for her birth. She did not seem really real when I saw her. The physical recovery oddly was easier because I was prepared for how much it would hurt. I cannot take diclofenac (if that's what it's called) due to ibuprofen allergy and I think this does make a difference - to get up to NICU to see DD I had to have oral morphine to get from the bed to the wheelchair, IV morphine before that (after I came round from the GA).
Oh yes, I got incredible trapped wind in my abdomen both times, like all these different balloons of air underneath my skin - I had no idea this could happen! First time it was too painful to eat while I was in hospital. Having the catheter and the canula out, not nice. They come along and jab a shot of something in your abdomen every day (to stop clotting, I think? - not sure).
I am sorry, I have written this in a bit of a scary way! I don't mean to tear in with the bad stuff. But I do wish I had known some of the negatives that were possible. The massive plus side is of course that both my children and I are alive and well! That would not be the case if I/they had not had the option of a CS birth.
This is just how it was for me and is naturally coloured my the sense of regret that I did not deliver my babies naturally, as it were. From what I know, a planned CS is far better, and I did know one other girl who had a CS around the time I had my first and when I said about the scar hurting she said 'Ooh yes, I got out of bed and thought, ooh, that hurts' like it was a bruised shin. And she opted for a planned CS for her second, no question.