Re: 4 days late but no pos. test?
If you weren't charting your temps to know when you ovulated, you might not be late yet. You could have ovulated late. Not sure if "kind of lazy NFP" means you're charting your temps or not, and you didn't really clarify. That said, I did have a cycle before this conception when I knew my ovulation date, and still AF came 4-5 days late, no positive tests. It could have been another early miscarriage for me, with HCG too low for the test to pick up. But I don't know for sure.
joyful mom of 9 blessings