I’m so hurt and upset and don’t know what to do.

Me and my ex have a 2 year old son. We weren’t officially together(we broke up a few months ago) but we still acted like it and planned on being back together. He was moving to another state and i was going to go with him (I’m staying with my mom right now). Whelp, i found out I’m pregnant again like a week ago and his reaction was good. He was saying he’s super happy and we’re definitely going to make this work i have nothing to stress or worry about blah blah blah. But now the past few days he’s been super distant and just showing me he doesn’t want this. He’ll post stuff on Facebook about finding “the one” as if he’s not over here telling me i am that one. This is my fault for snooping but he’s on my phone plan so i checked his call history and he called his other son’s mother at 3 am, it was only a 3 minute call but why are you calling her at 3 am? He hasn’t called her in so long and it’s not like his son was awake at that time to talk to him. Then he was on the phone for 3 hours the day before to some number i couldn’t find anywhere on his call log. And that was at 4 in the morning. He barley talks to me anymore and when he does, it’s short. I just don’t know what to do, I’m going to try to find my own place but that’s easier said then done. I want to make sure my kids are in a safe environment. I just don’t think my mom will be willing to allow me to stay here until i find a decent place. Which i guess i see her point, it’s not her job to provide a place for me to live anymore especially with kids. (I’m 21 FYI) however, i didn’t move out with my son’s dad until he was 1.5 years old so I’ve only been out for 6 months. So she’s used to living with my son. I don’t expect her to allow me to raise another kid in her house, I’m just hoping she’ll allow me to stay here until i can find a place. I’ll be sure to be out before the new baby, but i have a feeling she’s not going to be there for me at all and tell me i need to pack my stuff up and leave right then and there. Idk what I’m trying to get out of this post, just a rant i guess. I understand my mother doesn’t and shouldn’t allow me to just live in her home with children (just want to add i do give her money each month as my rent and fully support my son and myself) i understand i should have been smarter, so please leave out the negative comments. I already feel like a failure.