What's a "Bimple"?
Do you mean "Pimple"? Is it a raised bump? Do they ooze anything? Look like they have a "core"?
Can you see anything that indicates a stinger, like a bug bite?
Do they feel hot to the touch?
They look more like scrapes to me... like someone went rolling/crawling across the yard and encountered a rock or some sticks...
They don't look red or inflamed in the picture - but I'd keep a close eye on them.
Also, check the yard for bugs - ant hills, bee hives, etc. Could be a bit of some kind.