Period is ten days late

My period is 10 days late and my cervix is high, soft and closed. I am testing negative for pregnancy. I am getting nauseous., heartburn, my boobs hurt, I’m exhausted all the time, and I’m very gassy. I’m getting bloodwork on Tuesday to see if I am pregnant. I was just wondering what could be causing me to have a negative test when I’m 10 days late in my cervix is very high and soft when normally around when I get my period my service is extremely low hard and open. ovulation was confirmed with ultrasound and bloodwork by Doctor. I ovulated on December 1st.