Is it normal to feel this way?

I just found out that my brother (who I am estranged from and haven't spoken to in a year) and his girlfriend are pregnant. They are due in February, which is when I would have been due, but I had an abortion in July. I had the abortion because I had just graduated college and had started a new job and broken up with the father of the baby. I regret my abortion in some ways and in other ways I don't, I'm grateful not to have a child at this point in my life. But when I found out my brother was expecting right around the time I was due I just lost it. It was like a slap in my face. I feel like that should have been me and my bf having the baby, giving my parents a new grandchild, going through the joys of a pregnancy etc. but then I remind myself that I made the choice to have the abortion and I hate myself. Is it normal to feel this way?