Pregnancy possibility?

So I'm now 8 days late, took a pg test at 6 days late but bfn. Still feeling really dizzy and nausea plus really tired and v mild achy pains down there abit like period pain but nowhere near as bad! Dr told me to test again in a couple of wks but that if I was pg it would show up by now. Any 1 else had quite a late BFP?