To get a loaner phone, your phone would need to be sent away for repair. If that is the case, you would need to go back tot hat store to pick up your phone and return the loaner. You can always see what your tab is at and maybe just go buy a new phone.
If you're taking your computer, most of the smartphones (if that's what you have) come with a tether to connect your phone to your computer. You can use that in the interim to charge your phone, but make sure your data is off or be in for a big bill!