Q: Wireless mouse won't track

I Have a wireless mouse for my IMac computer and turned off computer and mouse and keyboard to go on vacation.  Now mouse will not work.  Will connect and will right and left click, will swipe screens but mouse arrow shows up black on screen and won't move.  Batteries have been changed.  Don't have another mouse to connive to computer and dont know how to use computer without a mouse.   Please help....frustrated!