I agree with everyone else, re-arrange it! My first was a week early and a textbook delivery. I was out of hospital in under 24 hours. I did manage to go to a friends wedding a week later, but I was still on a bit of a high really from the birth. A week later, at home, I was bleeding heavily, in pain, struggling with exhaustion, etc. My second, I was a week late then in hospital for 6 days. No way would I have been able to go and get married the following day. I had a third degree tear, was breastfeeding with only a 20 minute break at a time, bleeding heavily, bleeding from my nipples, sobbing constantly, could barely walk, it hurt to sit down….. I was a mess, I don’t think I managed to get into the shower for a week! With my third I was 8 days later, suffered a 4th degree tear and severe blood loss. They wouldn’t let me leave hospital for nearly a week because I was so ill. There is not a cat in hells chance I would have made it to a wedding.
No two births are alike, and for every woman that tells you it was dead easy and had no issues, you are likely to have 10 women telling you there’s just no way. Realistically, the norm after birth is to be bleeding heavily, exhausted and in pain.
Please consider trying to rearrange the date with suppliers as you’ll lose everything if you wait and have to cancel at the last minute. At least this far in advance they are likely to still be able to book someone else in on the date.