I'm Puzzled

I could have used the flash, even though I have a cheap make speed light http://www.linkdelight.com/E4M-GODOX-TT520-Speedlite-ThinkLite-Electronic-Flash-... there are about 7 levels of flash intensity. I think the light on the left is the wall so i could have even bounced the flash. I dunno!

I have never tried the delated flash technique, even though I understand they use it in sports photography. Will have a go trying that.