I just took 800mg of ibuprofen at 7:30am pdt, can i take an aleve (naproxen) 220mg, as i am having extreme back pain?

Mix it up: Treat the different components of your pain with different medications and modalities. You'll get the best relief. Your back pain comes from irritation of nerves, muscles, other pain generating structures (trust me here) and no one medicine works alone. Add a dose of Tylenol (acetaminophen), apply ice, try some gentle isometric motion (squeeze and release your belly). See a doc if still in pain