Honey I'm in the same predicament.
A month after my daughter turned 2, she all of a sudden started waking at night and would come to our room. It started about 430am and got earlier and earlier to the point she refused to go in her room at all at bedtime, wanting to go straight into our bed.
She started saying she was 'scared', and I had no idea why.
Even to the point of not going into her room to play.
I ended up completely moving her to another room, setting it all up as a 'big girls' room, took a lot of settling to get her to stay on there, we played in her new room for days before I attempted her to sleep in there. And she has started waking having nightmares too.
I have no 2 due in less than ten weeks do I hope it's sorted before then!!
Good luck x