Why did IOS 7 take up all the space on my iPhone?

I updated it last night, and it was 2.8 before updating. After, and as of right now it's 6.3 GB. What happened! It's saying I need to update again but I don't have enough room to now! I even deleted most of my apps

Its rare, you need to visit the service center of apple.
there's no other way.

Unfortunately, that's how they get you. I will not be updating my iPhone to ios7 because I know I don't have enough space and I don't want to delete my apps only to re-install them after it's updated -- too much work. Besides, it's my belief that it's Apple's way of forcing you to upgrade to a more higher capacity phone.