Last night at around midnight I checked on Cassi and when I opened up her egg box to see how she was doing there was a single egg lying underneath her. Mostly she looked indignant that I had interrupted her so I put the top back on her box and left her overnight expecting for her to lay the rest of the eggs by this morning. But, when I went to check on her about a half hour ago there was still only the one egg, which turned out to be infertile. She has been on moist moss, has readily available water and isn't swollen. I can feel about 10 more eggs inside her. Should I be worried? How long does it usually take for snakes to lay?