Test Again or Wait

Okay so I had a miscarriage last month & I've been intimate with my SO since but now af is 3 days late & I'm feeling anxious that something may be wrong. I tested twice this morning & BFN for both. I keep getting waves of nausea, I'm always hungry & tired or more like drained & I have sore nipples not boobs(weird). I want to test again but don't want another BFN & thoughts??