Cache Creek Animal Rescue

I have a stray pregnant cat that has been showing up on my deck for a few weeks now. I have been feeding her. I have no idea if anyone owns her…I’m thinking no. I don’t know what to do for her. I feel so bad for her. There’s also a stray intact male cat that runs around here as well. I don't know if he has an owner either. We have many predators here in my township area in New Lenox. I have a box with a heating pad out there for her that I put out today. She’s sleeping in it right now. She lets me pet her, but has snapped at me a few times. She looks almost ready to have the babies. There’s no way she’d let me pick her up. I already have 2 senior dogs & took in a homeless cat a few years ago. What do I do ? Is there any help for her, or is she on her own? I don’t want the foxes or coyotes to get her or her babies when they’re born. I’m heading out to work in a few hours, and don’t get home until 2 am or so. Thanks for your time, Dianna