not being able to cum

Hey ladies. I'm married and ttc. I woke up Sunday am at 4am to a peak ovulation. We had sex Saturday night. (We aren't used to this much sex). We tried sex Sunday and he just couldn't cum. He said he was turned on it just wasn't happening. 😖 now it's Monday. Is it too late now you think to have sec during ovulation? I heard it's like only a 13 hr window.