Is my new lawn going wrong?

Good Morning Guys,

I have recently moved into a new house 10 weeks ago, My developers put down a brand new lawn for me and told me to continue watering it even if there was some rain. I done this to the extent the the grass started to grow really fast! I am now 10 weeks on and because of the weather haven't been able to get out to give it a cut. I have been told the next chance i get to give it a trim with a strimmer and apply some feed to it. What dpics attached.

 

That lawn is way/way to long! Should have been cut regularly up until recently.

As JWK says, dont feed till spring.

 

Welcome to Gardeners Corner Craig. You can also stop watering it or it will rot. The roots will have established by now and and dew or rain will supply what it needs over the winter months.