That's just showing a prediction. What is your actual battery life (how long off charge, how much screen on time, and what are the main power users)? If you use the little 3 dot menu you can tell it to show the full device usage, i.e. including screen, radio etc. Show us some real results rather than a prediction and we'll have a better idea of whether it's normal. Don't forget to say how you set your screen brightness.
Actual device life will depend on how you use it and where (poor signal or a lot of hand-over between cells uses more power than sitting in good coverage) so it's quite hard to compare different people's usage.
If you've only just got it and have been using it heavily then the phone probably thinks that's typical, and may be predicting a short life as a result.
