Trepidation

Great news, I think.  We just found out our insurance covers 80% of one IVF cycle.  I was really excited to find this out at my first appointment on Friday.  Since then, however, I've been anxious.  I have no idea why.  We were talking about IVF, granted we were talking about giving ourselves another year to try naturally so this is kind of sudden.  But, it was our idea.  Why now do I have what I think are doubts about this?  It will be so much cheaper, and if it doesn't work, we won't be in a huge heap of debt.  If it doesn't work we can do another FET, depending on a few factors, and still not be in a huge heap of debt. The anxiety continues.
I know what the process entails, it's hard.  It's draining.  It's emotional.  I've chosen a brand new clinic, maybe I'm not certain they are good enough?  I know people that have gone there and that have been successful.  My doctor recommended them.  The anxiety continues.
Maybe I don't want a second child after all?  I'm not sure if that's possible, but why do I have this doubt?  I'm trying to pin point this and I need to ask myself if I'm ready for the demands of another baby/babies.  Our world is currently pretty serene.  Am I willing to flip what I know on it's head and start over?
Is the anxiety stemming from the fact that we'd be doing this to ourselves on purpose?  I DO want another child, but:
I know the heartache that IVF and failed FET bring, maybe I just don't want to go through it again?  Are we crazy to undertake this knowing that maybe one day it will happen on its own?  So many questions.  So much trepidation.