Yes it is possible! I am in my third year PhD as well and I have been able to successfully self petition for EB2-NIW. I had no citations at the time of my petition. I had only one publication where I was not the main author. It is very possible. Just make time and read about it.
Hi Doc Phebe, a lot of others like you are in the same situation. So you are not alone. We are here to support and provide the necessary resources as well. Please feel free to reach out