I recently finished my PhD in Developmental Biology in the US, but I left a couple of experiments completed prior to finishing the paper. (This paper was developed during the course of my PhD and has had numerous changes).
I have since finished my PhD and my supervisor started to take my paper and made decisions on it. He never once asked me for my Drosophila collection, and we never ever discussed the paper and how we could finish it. I became depressed as he treated like I am stupid, even though the paper was almost done and it was worthy of a high-impact journal... He never seemed to trust in my capabilities.
I have since realised that he found a new grad student to finish those experiments (that I could perfectly have done faster and in a much shorter time)... and now (almost a year later) my paper was submitted. Unfortunately, he decided to make the other PhD student the second first co-author of my paper.
I would like to hear some opinions as I don't know what to do. Is this going to impact my future career? I also don't understand how someone that knows deep inside that I am the first author of a paper can do this?