Stray in labor or getting ready to be, question

Okay, I'll make this quick since I'm trying to keep an eye on her but I have a few questions even after looking through info sites.

1. She wants to be cuddly but she can't settle with one spot she moves from place to place. The thing is I have her nesting box, food/water, litter box in two big dog crates connected and she is going insane to get out. Should I leave the area so she isn't wanting to get to me and maybe she'll settle down a bit?

2. She keeps going in her litter box and pees a bit but twice she appears to be trying to poop but nothing comes out, is this contractions just really far apart? I'm worried if I leave she might have one in her litter pan.

I have a small storage container set partially on a heating pad just in case it's needed, she has food but I had to remove her water as she was spilling it out everywhere but I offer it to her every once in a while. I'm stressed that she wants out so bad but the basement is unfinished and I don't want her going into the wall or somewhere hard to get to her.

Sorry I'm just freaking out a little, it looks like I'll be up for a while. Any suggestions would be great and thank you guys in advance!

Oh, one more question. Should I remove her litter and just put paper towels in the bottom just in case? It is non clumping clay litter.

I dumped the litter, sanitized the pan and lined it with paper towels, cleaned up the food she dumped everywhere and gave her some fresh. Then I left her alone for a few hours and when I came back down just now still nothing. She hasn't started pushing and is content, she licks at her lady parts then chills for a bit.

I might just sleep down in the basement, I'm more worried about her making a giant mess as she has been doing today lol. She did poop after I emptied her litter so I cleaned it again just now and relined it.