A Book recommendation:
7 steps to a pain-free life : how to rapidly relieve back and neck pain using the McKenzie method by Robin McKenzie
If you haven't read this book, you should right away. It goes over a treatment method which most Physical therapists will teach you, but does so in much more detail that you would get from a 1 hour session with a PT. It is worth going to a PT, for sure, but get this book as well.
The McKenzie method can be summarized as careful bending backwards (aka extension) but there is much more to it than can be summarized in one sentence. In addition to the stretches they prescribe, there is also a range of useful information, from how to sit correctly, to how to cough with less pain. Don't just read an online summary - get a copy of it yourself. Most libraries have it, and it's easy to find for sale online (click the link at the start of this post, for instance).
The book certainly presents itself in a slightly too self-aggrandizing tone. Reading the book, you may start to wonder a bit if it's some sort of snake-oil miracle cure, which I assure you that it is not - I know many people who it has helped. BUT: it doesn't help everybody, and those it does help don't necessarily find them selves completely cured. Myself, for instance. I'm glad I read this book, but it's only improved my situation maybe 20%. But every 20% counts!
Maybe you will be one of the lucky ones who find this is a complete cure to your problem. Maybe you won't. But it's only 300 pages, easy to read, and extremely cheap. Give it a try.