That damage is not Thrip damage. Seems to be,IMO, some sort of chewing bug. Slug,snail, cockroach, grasshopper, if you have any of those around. Can't say for sure what the Black flying insects that you see might be, I would guess they are fungus Gnats. Thrips are so very Tiny you would have to really look very very carefully to see them.
Let' see what others have to say.