If the ring doesn't work out, you might consider an IUD. There are a number of us on here with them. I have the Mirena (low dose of progestin), and some of the other women here have the Paraguard (no hormones).
http://www.tfproject.org/tfp/ladies-...-you-know.html
To be honest, insertion hurt and I've had some cramping since then, but it doesn't seem to be anything a couple Aleve doesn't handle. Looking out over the long-term, the pain has been worth it for a birth control method that lasts 5 years; the Paraguard lasts even longer.