She's definitely mature enough to be gravid. Can't tell age from size of female- too many variables. Gravid females usually stop eating right before
depositing eggs, but not always. Also, gravid females get a little lumpy in the
belly area before they are ready to start digging. Lumps are the eggs.
Good luck
She looks gravid, but maybe just a tad bit skinny. I would try to feed her some worm variety to fatten her up just a bit to help her out if she is gravid which she appears to be.