my phone will not turn on. It blinks with the apple logo when I try to reboot it.

I have charged my iphone over night. Tried to reboot it by holding the volume and power button ... It continues to just blink the apple logo and will not go further.

I have logged in apple and downloaded the most updated version of iTunes. But I'm not sure the last time my phone was backed up to the cloud.

Really hoping not to lose a lot of data. Any help is appreciated!