You might find this thread helpful! I was wearing DD the day of surgery, as long as you take it easy you'll be fine. Is there any specific reason they've said not to lift anything heavier than your baby for twelve weeks? Just that it's normally fine to lift carefully much earlier than this - lots of women have toddlers etc that it's just not possible not to lift at all. I had to lift my 15kg toddler within a week of the surgery (very carefully mind you), and was back carrying him again by about 6 weeks. She's about 14 weeks now, and I'm pretty much lifting anything that I lifted prior to surgery, so unless you've had something beyond the norm, I would take the 'standard' advice with a grain of very careful salt.

You might also want to look at thebabywearer under the 'traditional babywearing' section for specific advice on wearing kangas (which are pretty much worn the same way as a rebozo) - but anything that is tied away from the wound site will be fine.

Congrats on your little one!