I hurt my middle back. It's a constant pain but hurts very badly when I inhale. It feels like the pain is coming from the middle to slight right of my back. It's excruciating to sit or stand. I don't know if I should go to a clinic, the ER or wait it out.

And you would wait why?? Go to the ER! It could be kidney-related or your ribs or your backbone and you might need a cat scan or MRI.