Problem with storage on iCloud?

I have an iPhone and am using the 5 free GB of data given by iCloud. According to the storage info in the settings, here is my storage through iCloud: 1.5 MB for camera roll and 5.9 MB with mail. However, the phone says that I'm using up 2.5 GB on the iCloud. Where is this coming from? Is there anything else taking up storage that I'm unaware of?

Go to Settings > iCloud > Storage & Backup and then Manage Storage.

That should show you a detail of what is taking up your iCloud storage.

1.5 MB + 5.9 MB = 7.4 MB = 3/4 of a gig used, I'd be asking Icloud for some answers not here.