iPhone is stuck on plug into iTunes screen

I plugged in my phone to iTunes last night so that I could update it over night, but when I got up this morning it was on the plug into itunes screen. My phone has been stuck of the plug iTunes screen for a couple hours now. I tried turning it off and back on again, but every time i do that it returns back to the "plug into itunes" screen. I have tried plugging it into iTunes atleast 10 times, and nothing happens on itunes. It doesn't show that there is a device being connected. I don't want to lose all my data because I haven't backed it up yet... If any has any way of fixing this please let me know, I really need it to work. Thanks.