Why Does My iPhone Think I'm Using More Storage Than I'm?

I went to concert recently and I wanted to take loads of photos and videos. To make room for all this, I decided the best way to do it was to delete my apps and music and then once I'd transferred the photos get everything back again. So once I'd moved all the photos and videos to my iPad, I deleted them all from my phone. When I went to get everything back again, it said I didn't have enough room left to do so. I looked at my usage, added everything up and it came to just over a megabyte. However where it says how much storage I've used it says I've used six megabytes and only have around 100 megabytes left. I no longer have enough room to keep everything I'd like on my phone. So why might it be doing this and how can I fix it?

Videos take up a lot of space/room. But something is way off. IPhones have 8, 16,32, 64 Gigabytes not Megabytes. One song can be 4-7 megabytes. A long vid can be 50-500 Megabytes. Go into Settings > About and see how many songs, vids, photos, apps, and the important one the Available section says. If Available is showing like 100-200MB, yeah you're bloated and full and you'll see a warning pop up on the screen soon. You need to offload onto a PC with your iTunes and then place back stuff one at a time. Happens to everybody. Best luck.
http://www.imore.com/...ival-guide

http://mashable.com/2013/09/25/increase-phone-storage-space/

http://www.everythingicafe.com/how-to-manage-storage-on-ipad-iphone/

Something is obviously wrong, it happened to me too. Please restore your phone and back it up.