No sleep momma

I have a 17mo. For the last few months she keeps waking up every few hours after she goes to bed. She wakes up crying. Sometimes she goes back to sleep on her own but most of the time she doesn’t. I either have to stay up with her or put her back to sleep in my arms. She will sometimes be up for hours letter times just half an hour. Shes also teething. She’s a late bloomer with her teeth and doesn’t even have half of them yet. I’m not sure if that has is a problem. I also had a baby 4 months ago. Another possible change for her. I’m not sure what to try anymore. She will just cry as if something is wrong but nothing is. She has a pacifier, bottle and blanket but it doesn’t help her. Any other moms go through this? What did you do? I need some help. She is also started to just cry for everything. And I figure is regression from having a new baby but what can I do to help her move forward so we both get sleep. She’s not sleeping enough and I realize that also could be a reason why she cries so much during the day.