Is his mom trying to scare me away?

I got to meet my boyfriend's family at Thanksgiving. I recently met his son for the first time who's 15. His son hasn't really showed any interest in bonding with me and very attached to my boyfriend which is fine. I know he has been through a lot when it comes to his biological mom. I've been really supportive. I was at first wondering if he was being sketchy because I spent the night for a week and every night and he was getting upset because he was getting up to go to his sons room because his son was calling him and he didn't tell me what was going on to not embarrass him and respect his privacy. I knew in my head I was probably overthinking it and when I posted about it some people were suggesting that his son is probably having nightmares or accidents that he's helping with and that got confirmed by my boyfriends mom. I didn't ask. When I met this woman she literally pulled me to the side after a few hours. I get she had a few glasses of wine but she said she wanted to talk to me. She told me I was pretty. I said thank you. She said that my boyfriends ex wife was also pretty. I didn't know what to say. She said she doesn't trust my boyfriends taste in women after what his ex wife put her grandson through. She told me she's not trying to be that MIL and if it was just him she wouldn't care but her grandson is involved and the last thing she wants is him having more trauma. I told her I would never hurt him. I've been trying to bond with him. She asked if we get married do I think I come first in her son's life. I was just taken back. She said "My grandson is first. He will always come first. Are you okay with that? Even if you're the wife, he's first." I said I understand kids come first. She said my boyfriends son can be clingy towards his dad. I've already witnessed that. She asked am I okay with that. I said yes. I've already witnessed that. She said he still has nightmares from his past trauma. That he's a bedwetter because he's been through fucked up shit. Can I deal with that. I said yes. She said he's been through things that will probably effect him into adulthood. If my boyfriend has to put his adult child before me and I okay with that. I said yeah. She said "Okay. We'll see. I'll believe you for now. Just know if you hurt a hair on my grandson's head I'll kill you. Then my son." I didn't know how to respond to that. She was kind the rest of the holiday. She even gave me a hug on the way out. Was she just trying to scare me away?

@Chantelle eh I don't want him to go no contact with her. Besides that she was nice to me and I can tell my boyfriends son absolutely ADORES that woman.