Uncertainty is killing me!🙄

emma🖤boy mom to two 👦🏼👶🏼💙
I'm so frustrated right now! 
9 days late, no sign of AF or any signs of her coming. However 2 negative pregnancy tests - one on 16th at 7pm (thought may be why) but one of the 21st first urine of the day ☹️
I've got tender breasts, nausea (not enough to be sick though) & EXTREME tiredness!! 
Is it possible still to be pregnant, like having symptons but negative tests?
Ive booked in with Doctor for next week so will be 15 days late when I see them- probably take a test again the morning before? Please share any experiences and any advice! Pulling my hair out!!!!