I'm no expert but it looks like a lot of very leggy sprouts meaning It's probably not getting enough sun. In my experience, cilantro needs tons of hot sun because I've always had somewhat leggy cilantro.

Are you sure that is cilantro?

FataMorgana

Yes I'm positive it's cilantro I tried one of the leaves and it was good! But they're falling now!

Too wet, not enough light, too crowded... Any of these could be the culprits and are often problems for people growing indoor herbs.

If you have seed left, do you have a place you could direct sow some seed outdoors? You would probably meet with more success in doing that.

FataMorgana

And if that is basil alongside it is also too crowded. Basil transplants better than cilantro and you can transplant in little clumps.

You started way too many seeds together. If you pull it up, how are the roots? And did you underwater? I've had cilantro bowl over from being too dry, too.
Like Fata asked, I'm wondering if that is actually cilantro too. If it is, then did it ever grow true leaves? I ask because they all look like cotyledon only.....no actual cilantro leaves.

I would start over at this point in new soil. I'm not sure of the pot size but if it's about a 6" pot, I'd plant about 8 seeds total spaced out and go from there.

I'm attaching a photo of my cilantro -- note the leaves? This was three seeds started in separate cells and I bunched them together when transplanting. Got really lucky as I have never successfully transplanted this before.