I hear one of my eggs chirping...

No, don't be alarmed that only one is chirping.  You just have a "talker".  It's ok that you candled it but after day 18 I would try not to open the incubator.  This is when they go into lock down and you really should leave the lid closed during this time.  Good luck with your hatch :)

No problem.  Hope you have a great hatch :)

If they are pipping, they should be doing fine.  Just keep an eye on them.  Make sure the humidity doesn't get too high or low. 

We've actually had that happen to us before, had their mom start incubating them and didn't realize until I went to check on them and there was a little chick sitting in the slot in the turner.  I know its nerve racking when they start hatching, and the hardest part is keeping the incubator closed.  Just know that if you get the urge to intervene make sure you are positive they really need your help.  It's easy to end up doing more harm when you think you are trying to help then just letting them make it on their own.  I had to learn that the hard way.

Trust me I completely understand!  During our first hatch, I didn't want to go to bed when they started pipping.  I would say I saw the egg wiggle!  And my husband would think I was crazy.  Just know you're doing a great job watching out for them and I'll say a little prayer for you.  Keep me posted on how your hatching goes.  Pretty soon they'll start zipping :)  Sometimes, though they pip and it might take a little bit for them to start zipping.  It's hard work for them so just try and be patient.  Sometimes when they slow down, I will tap lightly on the top of the incubator.  That stimulates them a little because they think they're "brothers and sisters" are hatching so it's time for them to hatch too.  My husband also thought that was goofy but he's seen that work sometime too.  Good luck and enjoy your babies!!  Oh and post some pics :)