Hi Juliette,
As others have said, you're definitely not a failure, you ensured your little boy was born safely.
I have 2 boys, Jacob (2 years) and Noah (15 weeks). I had an awful labour with Jacob, lasting 37 hours. I tried for a home birth but transferred in when I was fully dilated as he was stuck. The contractions were truly horrendous, absolutely agonising. He ended up being delivered by ventouse and forceps but I was in theatre and prepped for a c-section - it was only because I had a very skilled person using the ventouse and forceps that I had a vaginal delivery.
I was scared coming up to Noah's birth, more so than with Jacob's after having such a rough time. It was totally different though, much quicker, and the contractions felt different, not like I was being tortured, thank God! I had mild contractions overnight, but only a couple of hours of stronger ones before he was born. I just used TENS. Most people I've heard from had a better time of it second time round too. Although your baby wasn't delivered vaginally your body still went through labour, so it will be a lot more geared up for birth than first time round.
I was concerned about not coping with 2, as I found it tricky to keep my patience with Jacob sometimes, but I really do think all mothers feel like that - no-one can wind us up like our children! So far it's been OK - the first few weeks were pretty tricky (I'm not good with sleep deprivation!) but once Noah started sleeping through the night and got into a rough routine it was much better.
It may help you to go through your labour notes with a midwife - I did this after I had Jacob, and found it helped me. It made me realise what I had achieved although the birth hadn't gone how I'd hoped - I felt I hadn't experienced everything and was a bit of a failure as I didn't feel him come out (I had an epidural by that point).
I hope you can both come to a decision you're happy with. God bless xx