Father's Day

I know today is father's day, but I dont know how to feel. I did tell all the important men in my life Happy Father's Day, the father of my child included. But then I started thinking about a lot and became irritated, so when he came in the house to change clothes before going out with his dad and later with his boys, I flipped out emotionally and we began to argue. I feel as if he is only acknowledging his first born son and not the child he has on the way with me. Am I tripping? Or is he being selfish?