Negative test after positive test

Hi everyone, I took my first pregnancy test 3 days before my period was due. The test turn out negative. Then I again took a test the day after my missed period and it was positive. I decided to take a test again after two days and it was positive but seems relatively faint line than previous one.☹️.... Today after 3 days of my last test I again took a test and it shows negative... I have pregnancy symptoms started few days before my periods was due and it is same today as well like morning sickness throughout the day... My body temperature is quite rosen and it keep fluctuating throughout the day between 96°C-98.5°C. My periods are never late in my entire life and the test also turn negative with all the pregnancy symptoms like nausea, fatigue, high body temperature than usual & food Cravings...

Please help me what is happening with me?