I suspect that you got a cable with a regular USB-B connector and what you need is a mini-USB-B connector. If the camera port is really small, it might also be a micro-USB connector, which is similar to what some mobile phones use.
A bit of Googling shows me this option:
That appears to have a micro-USB connector. You could have a look around to see if you happen to have a similar cable from a tablet, phone, e-reader or similar. Be careful though, cameras do sometimes use various special variations of connector, it might not be the exact same one.
The easy alternative of course is to use a SD card reader to get the photos from the card to your computer. Might be easier in the end.