Well, I'm 26 and have it. I don't think age has a lot to do with it, so I would say it's very possible you have it. I don't know if it's been confirmed that fibromyalgia is hereditary, but a few of my doctors say they think it is. You'll find that doctors really don't understand fibromyalgia, and getting answers can be really difficult.
However, it is possible that you're just growing and hormones are acting up throughout your body. It's also possible that you have Lyme Disease - have you been bitten by a mosquito or tick recently? It's certainly worth getting testing done, which normally just involves giving samples of your blood. Besides, you'll need plenty of tests to come back normal before doctors will consider diagnosing you with fibromyalgia.
For now, take hot baths to help with pain and try to get extra sleep. Cut all sugar and artificial sweeteners out of your diet for a while and drink lots and lots of water. Give your body a break from non-nutritious food so it has a chance to heal. Also, I've found that a Tens Unit can help with pain, temporarily. I found one for $40 on sale. They send electric shocks through pads you stick to your body where you hurt, and the electricity prevents the nerves from telling the brain you're in pain. There's no side effects, and you can use it whenever you want wherever you want on your body.