Jealous friend?

My best friend already has a baby girl who is 18 months, but she’s trying to get pregnant again. I am trying too and have had a bit of a hard time, a couple of early miscarriages, but we’ve been trying the same amount of time. I am now pregnant and has acted happy to me but I sense she’s a bit annoyed. She loved being pregnant and loves to tell me what it’s like, but when I told her a pregnancy fact she didn’t know she got really funny about it and said I should stop reading online. Almost feels like she wants to be the pregnancy expert and it has to be about her, not me. It’s very odd and she’s snapped a couple of times. Any idea what’s going on? I find it odd she’d be jealous when she already has a baby?