BFP to BFN to negative blood test but no periods

[Heavensbaby]

Hi Ladies,
I am very confused with my situation here and freaking out. I got a BFP on 6dpo (very faint) that got darker the next 2 days. I rechecked at 10dpo with the morning sample, expecting to see the darkest of the lines, was shattered when I saw a BFN! It has been BFN since then . Confused as ever, I went for blood hcg on 14dpo, the day my AF was due, and unsurprisingly , that too was negative. Today I am 17dpo , with no signs of AF and feeling very pregnant- tingly breasts, mood swings, tiredness, always hungry, sore throat, and lower back ache . Don't know what to think . Please help me with your thoughts.

 

[Heavensbaby]

If I am having a chemical, wouldn't I have bled earlier than my AF due date, since my line disappeared from 10dpo or before?