She should be fine- she is getting ready to have her kittens but it isn't time yet. You need to try and stay calm because she will pick up any anxiety from you and right now she just needs peace and quiet.
Your best indication to determining how soon she will deliver is when her core temp drops to about 100 degrees. After that happens it is about 24 hours or even a little more before the labor starts. But you need a rectal pet thermometer, your mom can buy one at the grocery store in the pet section. That is the best way for you to tell.
Checking on her every 10 minutes isn't going to help her much or you either, just try and relax and let nature take its course.