Please tell me someone else has felt this way

I have a 2 year old and am pregnant with my second child. Long story short, I'm due any time now and terrified to have 2 kids. I've been fine up until the last week or so, so I'm guessing it's just hormones messing with me. However I'm terrified that I may be getting myself into something too big to handle as I'm also a single mother. I'm completely on my own and I really don't know how I'm supposed to feel. So please, has someone else ever felt like this and had things turn out better than expected at least..? My son drives me up the wall most days so I'm nervous how I'll be with 2 little ones...