You heed to call back the masonry company that did the work originally. They need to make this right. Pictures may help people point you in the right direction for your conversation with the mason.

The concrete is unsealed which means it will always look weird while drying. This doesn't concern me. Exterior grade, unsealed concrete does stuff like this. The issue I have is the dip that allows the puddle. Eventually that spot will wear away a little faster or grow some green stuff that is murder to remove.

As millworkman suggests, you should be calling back the company to ask these questions.

Photos of what you are talking about would help.

Here is the brush streak:

Here are the green spots: Sorry it had just rained so that's why the rest on the concrete is dark.

This piece is next to an old piece of concrete, so don't mind that.

The concrete is less than 1 week old. It can take 1mm of concrete 1 day to cure. That means 1 inch (25.4mm) roughly 1 month to cure. This is very new concrete. The colour variation *might be a concern...but it might not be. It depends on the curing additives they used to speed things up.

The brush stroke is the same 'texture' as the area beside it but it is a much lighter colour. Is that where the 'dip' is?

The dip I did not take a photo of because there was no water lying in it so you couldn't see it. The brush stroke is very rough compared to the rest if you run your hand across it. I was told that they used a wet broom after rinsing it and forgot to ring it out before creating another stroke. Oddly, it is drying "whiter" than the rest of the concrete. May I mention, the green spots are only located on one side of the concrete. The whole section surrounding our pool (the majority) has not a green speck on it.

Concrete takes 28 days to fully cure. You may see some color variations during this process.