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Looks like sheep sorrel, Rumex acetosella. Can take on that red tinge as a reaction to some sort of stressor.....like cold weather.

ETA: weed and feed products are highly inefficient at addressing weed problems at the same time they are often overapplied and lead to groundwater pollution. Better to use a dedicated broadleaved weed herbicide....something like Weed B Gon. As these form expansive colonies all connected by a complex rhizomatous root system, I prefer to dig them out manually.

Dead weeds are always hard to ID and I'm lousy at it anyway. However, it's a nice broadleaf, which any basic herbicide will take out.

As you found out, Weed and Feed does a lousy job.

Get a nice, cheap sprayer. And pick up Ortho Weed B Gone Clover, Chickweed, and Oxalis concentrate at the same time. Mix as per instructions. That will take out 98% of the weeds you'll ever see in your lawn.

Proper feeding, at this point, is just any standard feed, but done on Memorial Day, Labor Day, October first, and (optional) when the grass is still green but stops growing. That will give you strong growth that helps choke out weeds.

Thank you both for the info. Will Weed-B-Gon or products like it work now this time of year or should I wait a little later in the year like possibly May to use the product ?

If the weeds are green and actively growing, it'll work now. If they look like the one above, that is currently not active and wouldn't absorb the herbicide.

My bet is that they're not yet active. :-) April will probably be better.

Regrettably, it does have to be actively absorbing herbicide. Right now, it may require two shots, which I really don't like doing as it's more toxic than it has to be and can take a toll on surrounding grasses, which don't appear in the above photograph. Fescues, in particular, can be a bit sensitive. Bluegrasses tend to be relatively bulletproof. :-)

That's fine, so if you want to treat it now, go right ahead. And definitely don't wait until May. But it's best to wait for full reactivation and daytime temps in the fifties. If you follow the advice on the bottle, they do recommend active growth to avoid overuse of the product and too much toxicity in the soil.

I'm not sure of your locale; for me, in eastern PA, perennial weeds don't get sprayed until early April (this year, probably a bit later; spring is late regardless of the calendar). Further south, that will be earlier.

Actually, that's a good point. If you're a southern grass person (Bermuda, Zoysia, St. Aug, etc.) your herbicides will differ. In that case, you'll need to ask @dchall_san_antonio or at the store as the one I recommended will do a heck of a number of most of the above grasses. And some of them are very sensitive to herbicides in the first place, and some are practically bulletproof again.

For northern grasses (fescue, rye, bluegrass), the Ortho I recommended is just fine, but fescues can be a bit sensitive to over-exposure, so local damage is possible if you spray too much or too often.

Sheep sorrel is native to zones 3-9, so it could be anywhere (but in the lowest zones, it's unlikely to look that shabby even in winter).

I am from RI so maybe I should wait till first of April

Looks like Rumex acetosella to me too. Edible if that’s any consolation.

Then you have a northern grass. That would be fine.

So now would be a good time to spray them ? Even if I have to do it twice

You can, but it's really too early. Absorption would be limited, and even with the half-asleep fescues, it'd damage them (the herbicide will sit in the soil). It's better to wait a bit until active growth begins--but long before they seriously start to spread or grow like mad!

Thank you so maybe I will wait till temps are at least 50 degrees pretty consistently