help😩

My partner and I had sex the 14-29th everyday. My period was vetween there but i only bled for two days which is not normal. I took a test the 20th and it came back faintly positive but every test sonce has came back negative. Ive had extremely sore breasts and exaustion. Ive been fluntuating between hungry all the tome to not hungry at all and fluid has been my best friend. I am 98% sure im pregnant but i  havent had a positive since the 20th. Im not to to start again for two weeks. What is happening??