I just booted on to the OS X Installer for the 5th time and it actually booted all the way into the installer and from there I could restart back in to my main hard drive. Mavericks is working again!
I installed OS X Yosemite today on to an external hard drive and once it was done, I booted from the hard drive to test it out on my 2009 Macbook Pro. It worked fine, but there were some glitches, it being a beta and all, so, I shut it down to boot it back up to Mavericks. When I tried to boot it up I got the Yosemite loading bar instead of the Mavericks spinning "flower" (i guess?). The loading bar goes halfway, then gets stuck and nothing happens. When I go to the Startup Manger instead of saying Macintosh HD (the normal booting drive) it says OS X Installer. My recovery partition is there as well. What happened?!?! How can I boot back into Mavericks?
Thank you kindly,
Graeme

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