Missing Photos

I uploaded my photos from my iPhone to iPhoto. At the end of the upload process, while deleting photos off my phone, it froze for 20 min, and I was forced to quit the program. When I reopened iPhoto, the photos were not there; however, 10 GB of space was missing from my hard drive. Luckily, it didn't delete the photos from my phone, so I connected my phone again and re-uploaded my photos. It took up another 10 GB of space, making it a total of 20 GB for 10 GB of photos. I looked all throughout my photo folder, and I didn't find any duplicates. Where could the first set of photos gone. I'm on vacation, and I need more room for my next set of photos. Timely responses are appricated!

Thanks.