I’m happy for her but...

So my sister just told me she is pregnant with baby #2! Thankfully she told me over the phone though. I sounded super excited over the phone but I was crying in real life. I want a baby so bad. This is only my husband and my first month trying but I can’t even seem to get a positive opk. I’m on cycle day 18 and still nothing. I love my sister though and I’m so happy for her. I’m just scared that I won’t get to experience the same thing!