How is my iPhone 4 so over-capacity

I have a white 8GB iPhone 4, and whenever I try to add more music, it tells me it can't sync anything else onto the phone because it's over-capacity. I only have about 25 apps. Before, I had way more, and I've deleted all the apps I absolutely do not need and all the ones that take up a lot of storage. I can't remove any more apps I currently have on my phone because I use them all.
As for music and pictures, I have 304 pictures. I've had up to 900 pictures and videos with all the other extra apps and my phone wasn't over capacity.
I also only have 354 songs as well. Apparently you can have up to 100 songs or something. I've only had this phone since June, if that helps. I know that some storage is taken up by the software (iOS 6), but why is it claiming to be so full! I can't take any more photos or download anything unless I delete some things (I've already deleted everything I can).It's really frustrating, because I know that I have had way more apps and pictures/videos on my phone at a time.

Just saying numbers doesn't mean squat, you can have 1 video that bigger then 50 combined.

  • Why is my iphone over capacity? I only have like 9 apps and not even 100songs on it? I'm trying to add pictures to it but its saying its over capacity and its also going really slow, i've token out half of my apps and deleted most of my pictures too but nothing helps
  • Why is my iPhone copying the same video over and over? So I took a screen recording earlier today and when I went to send it, there were about 50 of the same video. I thought alright i'll just delete them. So I did. And they returned. I now have over 300 of the same video and it keeps copying itself.
  • Why does Netflix keep pausing and playing over and over? I'm using it on my iphone 4. And I have checked my connections over and over I've uninstalled reinstalled, signed in signed back and everything else that the troubleshoot website has recommend. And it's gotten annoying. It didn't start doing this as much until I updated the app before the ios 7 release. I'm currently using the trial for netflix and my laptop doesn't work so I can get it on anything but my phone.
  • Why Does My Itunes keep saying Over Capacity? I Have a16 Gb iphone and i currently have 1,140 songs which takes up 8 gb total according to itunes, keep in mind that i have over 1 gb free, so i decided to add a few more songs and tried to sync but then it said over capacity by 302 mb i don't get it, How can i be over the capacity by 300 mb if i have at least 1gb available?/ can someone please explain this!