I believe they can, it depends on how quickly your beardie has developed and how fast she has grown.
Firstly is "she" in with another beardie?
It can be very dangerous for a beardie to have eggs much before she is 18 months old, with 2 years old being even better.
The usual signs of a gravid beardie in getting bigger belly, if you gently palpate her abdomen you should be able to feel them.
When they are almost ready to lay you will usually start to see the outline of the eggs inside her on her abdomen, she will start digging around the cage insesantly, that is when it is essential for you would provide her with a lay box, for her to dig in and lay the eggs.
It is usually quite easy to sex a bearded dragon, here is a link:
http://www.repticzone.com/articles/sexingbeardeddragons.html
If it doesn't have bump, dimple, bump like in the pics, then it is a female! It's that simple.
Hope this helps, good luck!