Can you see the individual eggs making bulges on her abdomen yet?
If not, she either has only a few eggs, or she will soon puff up with a load of growing eggs. What you want is to see her experiment with digging in her nestbox, and after a while, one day she suddenly becomes skinny. IMO if she seems to have laid her eggs, she should have a follow-up x-ray to check for any retained eggs. Also, if she doesn't lay in time, she needs a visit to a herp-experienced vet.
Maybe others here can help you with the time period in which she should lay.