why did you up the temp to 39?? 37.5 was the right temperature. I always candle at 7 days, anything with veins or not sure stays in, totally clear eggs get binned. Then I close incie, and dont open it again until the 18 day check. I top up the water every 3 days, to maintain relative humidity at 45% for first 18 days, then adjust it to 65% for last 3 days.
On day 18, I candle again. Anything that is just black with an airsac stays in, clear, or half formed, dark line (called a blood ring) gets binned, to avoid the risk of bad eggs exploding in the incie (it makes such a mess and is a bio hazard). I put my hatching mat in, to prevent 'splayed legs' in new-borns. Drop temp down from 37.5 to 37. and humidity up from 45% to 65% . I top up the water, then LEAVE THEM ALONE. even if one or two hatch, it is best to leave them in for 24-48 hours until any stragglers hatch.
it is unlikely that you will see any chick movement, mostly because you need to candle for the SHORTEST possible time. The light can affect the growing chick, so a flash just quick enough to see if its fertile is all I do.
If nothing has even 'pipped' by day 23, I bin them, but usually open then to see if I see why they died, ie, drowned(humidity too high, small airsac), shinkwrapped (membrane drying out, air sac too large, relative humidity too low) mal position (breach). Temperature affects humidity, as the humidity is worked out to be RELATIVE to temp. If they hatch a day early, temp is half a degree too warm, lower it to 37, if a day late, raise temp by half a degree to 37.5 - 38, this is a sort of trial and error thing from experience of your own incubator/eggs.
Hope that helps
Using a broody girl is so much easier for beginners, as the hen USUALLY manages it all automatically