I am in the third year of my PhD and so far I have published one paper in top tier journal. I did all the work by myself. However after I finished everything, my supervisor told me that he would revise the paper and submit it. He put his before mine and added a bunch of people from another university. In the author contribution section, my name was removed from many sections until I was only responsible for experiments.
I learned about this only after the paper came back for revision. I asked him why he did it and he said it doesn't matter much because he mentioned that he, I and another professor contributed equally to this paper and I a first co-author. Also, during revision he gave around 10 extra references that I should add.
Eventually this paper got published and now I am working on another paper. Everything is super hard as I get zero feedback from him and he only wants to see a fully finished paper with a novel discovery, otherwise I should not bother him. He also gave my two of his bachelor students, and he literally told me to perform all of their experiments and make all the visuals for their dissertations. I can't even have a normal meeting with him, because he is always in a rush and trying to finish it as soon as possible.
I start thinking that maybe there is a part of racist behavior, as I am an international student and all the mentioned above only happened to me. My lab mates published some papers and the supervisor's name was always last (corresponding author). I talked to another young professor and told him about everything and he extremely disliked it. But he says that right now I can't do anything about it, because I am expected to graduate next year and my supervisor is a pretty big professor and I definitely shouldn't make him mad at me.
I don't even have time to talk to other people about this: I work with no weekends or holidays for at least 12h a day. What would you suggest? I really love research and for me it's not a problem to work overtime, however I feel like I am just being used.