I lost my digital pictures during upload, when using iPhoto?

Imagine your 15 again, and you and your friends had the best day ever. It was perfect you rode around in shopping carts, drove around in the car, and just quite plainly had a blast. Throughout the day you and your friends are taking pictures of said "best day ever" However, when you get home you upload the pictures on iPhoto and its taking to long and you press stop upload and then resume. And all your pictures from your precious day are gone forever. Is there anyway to get them back? Please