Yes, but I might be crazy, that's the thing. I could just be imagining it. I need your opinion. This is part rant.
There are no known incidents involving winged people, or people growing wings in the real world. so... the chances are you are not growing wings, in fact I would bet a great deal of money on you not growing wings, and my soul as well. Put simply, if you grow wings I will eat my hat.
First possibility: your producing the "Pains" yourself as a form of mental trick, if you have always wanted wings, this is the most likely possibility. (or if you believe in this kind of thing, a sign of past life or alternate soul, visit the otherkin/therian section for that, cos I personally think its a load of bollocks, and really can't advise on it.) I spent a long time in school wanting/trying to grow a tail, made my back feel very weird, but well... I never actually grew a one.
Second possibility: Something IS wrong, but its not wings. Its possible you injured yourself, and it happens the injuries were on were your wings would be. check how your sleeping, and if you wear a backpack frequently make sure its not stabbing you in the back, (as in, having something sharp hit your back when you walk. not literally knifing you) or too heavy. if it hurts a lot, see a doctor. the worst he will say is "nothing there".
...Though I will just say, on the off chance you DO grow wings, don't try to fly with them. The human body is not designed for flight and you will probably cause yourself a serious injury.