You've done a great job keeping your troubles from your kids, which is wonderful, so don't let up now, when you're so, so close to the finishing line.
If you have to fake a smile in front of them, then do.
Lindsay, I am sure you will be fine. You'll be back here on Monday saying that you got the all clear. Put the computer to rest, take a brisk walk or drink some camomile tea. Keep taking your zoloft, and you'll feel calmer, even if you don't feel 100%. We are all behind you, so please be good to yourself try to relax.