AF never came today?

So yesterday at 13dpo I tested and it seems pretty negative. Today AF never came 🤷🏻‍♀️ This app predicted that it was coming 2 later than usual to begin with (IDK why)

I have been having really odd symptoms like I was nauseous this morning and had a pounding headache, I got short and very very mild cramps last night and this evening that lasted like 20 seconds, my nips are hella sore, my lower back hurts, and I’ve had heartburn for 2 days now.

I don’t know what is happening at all, we aren’t like trying trying just being cautious when the app says high chance. Should I retest?