Dumb questions I'm sorry, please help

So background- last cycle I was 3 days late for AF this cycle so far I havent tested for a surge of LH... I was supposed to ovulate on the 13th... how long of a variation can there be before you should be worried you wont ovulate? My cycles have always been regular and it's rare that I have AF come even a day late... also is it possibly to have AF come but not ovulate? I know I shoudlnt worry about these things but we just got married are just starting out and it's the greatest fear I have that something is wrong with me... also we went to the beach and I forgot my tests is it possible I could have ovulated on the 10th and gotten no surge of LH by the time I tested on the 12th?