I’m at my wits end. Negative tests but I know I am pregnant!

My period was due 1st October, except for a small amount of spotting, there hasn't been anything.

My symptoms all mirror early pregnancy symptoms;

Boob changes - constant erect nipples, nodules appearing all over, darker and larger areolas, prominent veins.

Nausea - daily, worse in the mornings and evenings

Frequent urination - ALL. DAY. LONG

Tiredness - usually go to bed at 11pm, I'm falling asleep on the sofa at 7.30pm

Food aversions - Certain foods make me feel sick, some foods (potatoes) I cannot get enough off

Lower back ache & hip ache

Jaw ache - one sided, feels like it's in my cheekbone, giving me headaches

Increased heart rate - I wear a fitbit and my RHR has gone from 68 to 79 in the last 1.5 weeks

However, all my pregnancy test results have been NEGATIVE (last test was two days ago)

I feel different, I know my body, something is going on. I have a doctors appointment at the end of this week but if calculations are correct I should be 6/7 weeks. Is it really possible to have negative results but still be pregnant?