4 days late, when should I test?

I’ve been trying to get pregnant since my miscarriage in December😔 this month I had sex the night before ovulation and tried again the next day but partner wasn’t up for it, but I’m 4 days late, feeling nauseous but not vomiting around 6-8 pm the last two nights and my nipples have been extremely sore, I can’t wear a bra! They look slightly darker but I don’t know if they are just sensitive? They are always hard aswell when normally they only erect when aroused. I have been under a lot of stress lately but that doesn’t normally make my periods late it usually makes them early.