I've been sterilised at the age of 30, had to wait till 30th birthday (twice, but that's another story!) It is now a relatively minor op, in and out in under four hours, except the second time I had to have a general incase they needed to remove the fallopian tubes, just to make sure.
Seriously, I was sterlised when my son was three months old, my daughter just 15 months. That was what I wanted, but I fell pregnant 11 weeks afterwards. I couldn't go through with the pregnancy because that is what we had decided, two close together. I also had been sterilised when it was done under a general and a largish incision made, the wound became infected and the stitches did not dissolve, I ended up having them rem oved on boxing day, and taking all sorts of antibiotics etc, which were not recommended in pregnancy.
I didn't have a problem with the termination ( and still don't) but they managed to mess that up as well (7 weeks) and ended up haemaeroghing (can't spell).
I was sterilised again three years later, so I now have three clips on one side and two on the other, I'm sure that's why I can never go thru an xray machine without it beeping!!
Even depsite the problems I had, it was the best thing I ever did. I didn't want to be on the pill for another 15 years, it's great never having to worry !
Go for it!