Strawberry-like weed in lawn
Would anyone know what kind of weed the photos below show?
It's some kind of trefoil weed, I think, because the leaves come in sets of 3. And sometimes this weed produces a red thing that looks like a tiny strawberry.
You can see the thing resembling a strawberry in the first photo. Someone told me, though, that this weed is definitely not wild strawberry, but they don't know what the name of the weed is.
I'm also wondering if I should pull this weed out of my zoysia and fine fescue, or leave it? Is this weed nitrogen-fixing? I don't pull white clover out of the lawn because the clover is a beneficial nitrogen-fixer.
And the third question: What are those small yellow-orange spots on the bottom of one of the leaves? Is it some kind of fungus?
Here are the 3 photos: