i had my tubes tied when my son was a little over a year old. A lot of places will request that you wait for at least a year after the birth of your child just be SURE, but not all. I was breastfeeding, so i couldnt be put under anesthesia without having to pump for him, so i just decided to wait. I also only have 2 kids and i had mine tied at 24. I am allergic to pain medication, so all i could take was ibuprofen. When i first woke up i felt like i was in labor. But once i was able to take some ibuprofen it settled down a bit. The first day was pretty rough, it hurt to stand up straight and it ached a lot. but i mostly just slept. I was still groggy from being put under. They next day it just ached like bad cramps and i was virtually fine the 3rd day.
also note though, having your tubed tied is really only about 98% effective and that percentage goes DOWN as the years pass and your body works to repair itself. Studies have actually shown that an IUD (when placed properly and doesnt fall out) has a higher chance at preventing pregnancy than a tubal ligation. But again, that is when it is done perfectly. I personally know 2 people who have gotten pregnant with the mirena.