Is it bad I feel this way??

The facts. My husband and I have been ttc our first for a year and a half. I had a miscarriage a year ago. My sister, shortly after my miscarriage, became pregnant with her first. She was scared to upset me.

I was filled with joy for her. I love the little girl that was born on December 30th. Even though my sister said it was an accident, we both belive the baby to be a miracle.

My problem. I am sooooo happy for my sister. But I am also upset. No one understands how I am feeling and it makes me feel like a villain. My in-laws,when I told them about my sister, thought that is was sibling rivelry. No. I don't care the my sister was the first. I care that I can't seem to carry to term. I feel like I can't talk to my mom any more and she has been my best supporter in the last year and a half. She is to happy about her first grandchild, I can't trouble her.

Is it wrong to have these feelings??