i just had my first roll of film developed. It was kodak (non proffessional) 100 film, i had exposed (or at least i thought i had) 24 photos within about 2 or so days, then i immediately had them developed. the camera wasnt in any type of warm climate or bright light for a long period of time, and neither was the film. but when i came to pick up my pictures, there werent any at all. All of the negatives were completely dark, as if they had never been exposed. This is beginning to worry me. The camera is a nikon f3, and everything seems to be working fine. any ideas? I'll need to know kind of quickly because i only have a little while left before the return deadline.