It's scary for sure, but you'll find it soooo worth it.  
I've been a SAHM for 12 years now.  At first, it was scary - I was giving up my income, income potential, independence.  But I could not bear the thought of someone else raising my children, so I took the plunge.
At first, it was tight - didn't feel like we had the money to do anything, we called it the shock factor - you are "used" to a certain amount of money you think you need to live.  But you find all the money you save from not paying for childcare, gas to and from work, buying work clothing, eating out with coworkers, car payments because you wear your car out faster commuting, and it's not as big of a deal as you thought.
Do I miss certain things about working sometimes - absolutely.  I miss the interaction with the people I worked with.  I still have interaction, but it's more mommy interaction - not me as an individual interaction. (that's part of why I'm here)  But I wouldn't trade this for the world, I absolutely love being home with my kids.
I do enjoy getting dressed up and going out to dinner more now though.  It's more of a treat to get that break now.
Now you wanna talk super scary?  I'm going to home school my oldest next year.