You can get back to where you were by replacing the save file (which is usually a .srm file but I dunno what it is on a Mac).
Basically:
Find out what the name of your save file is (look for a .srm file somewhere in your emulator folder). For example purposes, let's say it was earthboobs.srm
Then go here:
http://fantasyanime.com/legacy/earthb_saves.htmFind the save you want, extract it, and rename it to exactly what your original save file name was - in our example you'd rename the .srm to "earthboobs.srm". Then move this file to where the old .srm was.
Load up your emulator, and if all worked out, you should be where you wanted.