I know that macmanx is helping you, so pardon the jumping in.
If you uploaded a single image and consumed the 3 gigabytes of space, the image was too large. Check the file size to ensure the image is a reasonable size such as 100K or less. It could be larger, but start smaller first.
If the image is too large, it will take a very long time to load, which could explain why you can't see it.
Remember, you cannot just click and drag an image into the post editor area. It must be uploaded via the Media Uploader (ADD MEDIA) and embedded into the post that way. Images hosted off your site may be linked directly if the source permits (not all do) by using the ADD MEDIA > INSERT FROM URL option.
I know it's confusing. Thanks for your patience while so many work hard to help you figure it out.