Regarding first authorship of my PhD study

I am a final-year PhD student at a Japanese university. I must be the first author of my main research paper in order to graduate. I screened 2400 bacterial isolates by myself for 16 antibiotics and six carbapenemase genes. I summarized all the data, identified all the trends, and did the statistical analysis alone. My professor only asked me to do the Non-metric Multidimensional Scaling (NMDS) analysis. This experiment was carried out from 2023 until now.

My professor kept me waitaing eight months for a reply, during which time my storyline for the paper was accepted by my three co-authors, who are associate professors. One of them, my former supervisor, accepted the storyline at the time but later said it did not meet his quality standards and that he would be the first author instead. I need to be the first author in order to graduate.

In addition to this, I have faced several difficulties in obtaining chemicals and have had to wait months for them. My professor always shouts at me and has come to hit me on two occasions. I am a woman.

Could you please advice? I feel very helpless.