If you are "we're" Jailbroken then it Sound like you have come to the time where a restore is you're only option , Jailbroken devices should never use the on board system reset on a idevice , I have advised people over the years not to do this as it causes massive issues with the device.
You have the loading bar on screen ? I would leave it as long as you possibly can , it could just be hanging , if it has been left and is still presenting you with a half loaded bar you could try to enter safemode ......
Unfortunately I do not think it will work , you have triggered off the "Reset" process
Your iOS has already been Jailbroken , that alone changed things and now it's struggling to rebuild the changes the jailbreak made.