There's an old superstition that says, if your right ear is ringing, that means someone is talking good about you, and if your left ear is ringing, someone is talking bad about you... then of coarse if both of your ears are ringing, someones having a pretty heavy conversation about you!!
If only it were that simple, and interesting! Unfortunately one of the most common reasons we get a cronic ringing in our ears is because of high blood pressure! Which can really cause you even more problems over time. I agree with STRIDERSPLACE, you should see a doctor, or hearing specialist if it's been ongoing, lasting more than 2 weeks. That goes for any illness or oddness with our bodies. We should always live by that old saying... "an ounce of prevention is worth a pound of cure".
It's also possible that you may have a wax build up in your inner ear. Which can also cause you a lot of problems, with ringing, and even your equilibrium (ballance). You may just need to have your ears cleaned really good. If you go to a Health Food store, or a Vitamin Shop you can find Earwax Cones for cleaning your ears at home.. it's actually kind of fun.. SMOKE pulls out the ear wax into the cone, you can actually see it! We should all do that once in a while as part of our grooming routine. Good luck! I know how irritating that ringing can become!