Hi Donna, and welcome!
Macro photography can be tricky...most people start out with nothing but a "blurry mess", so don't dispair.
The most likely culprit is a shallow Depth of Field, which you can read about here: http://www.dofmaster.com/dofjs.html
You can maximise your DOF by;
*Stopping down your lens (ie, changing from F2.8 to F11)
*Moving a bit further away from your subject
Another possible problem might be camera shake. You can limit this by;
*Using a higher shutter speed
*Using a tripod
Of course, if you stop down your lens, and up your shutter speed, you'll have much less light, and will probably underexpose your photo!
You will find that most macro photographers will use a tripod if they're shooting still life subjects, or will use a flash if they're shooting handheld. It's all about getting enough light to make a decent exposure.
As an experiment, try this;
Set your camera to AV
Set your focus to Manual
Set your aperture to F16 (to start with)...the shutter speed will likely be quite slow, but you'll have an increased DOF
Manually focus on your subject
Use a tripod, or bench to ensure your camera is still
Use the self timer, or a remote trigger to take the photo so that you're not phyiscally touching the camera when the shutter opens
Is the result is any better?