Finch Breeding?

We've had our two finches, a male and a female, for a month. They started acting odd, then started building the nest. We noticed an egg yesterday morning, so I did some research to see what to expect. What I read said that the hen will lay one egg a day (or 24 hours) until she has 5-7, and start incubating them after the third. As of now (36 hours later) there is still only 1 egg. I read that sometimes they get stuck and she can't lay. Should I be worried? Should I wait until tomorrow? I feel like I'm stressing them out by checking the nest so often.