weed in my new lawn (help please)

HI guys,

I,ve just paid a landscape gardener £300 to lay a new lawn, its not a large lawn and it did look lovely but after about a week the whole lawn is covered with weed looking type plants, can anyone tell me what there are please and is there a way of permanently getting rid of these or should I be asking the gardener to replace the grass as i deff dont want a garden full of weed and its not what i paid for, I was told this was top class lawn that was laid and never expected this.
I,m really hoping theres a quick fix of weed killer but looking at it i,m not so sure as the whole lawn is riddled with this weed type plant :(

 

is that not the lawn forming seeds? .... hard to see from the pics

if it is the lawn forming seedpods, you have nothing to worry about

 

thanks for that the gardener just been round and told me the same thing lol its cus the new lawn is seeded lawn he bought and we have had loads of rain the seed have come up, he said to leave it a week and give it a cut... glad thats ok i was really worried lol