Advice seeding lawn

Hi everyone,

I have really started getting into my gardening and would be really grateful for some advice. Been in my new home for a year now and had lawn laid for us when we moved in and it looked great. Now after the winter its not looking so good, i fed it at the end of the summer and always kept it at a nice length. 

After a wet winter i struggled to get it cut and when i eventually got round to it once the weather dried up it was pretty much brown underneath and very patchy. I have since scarified it and raked up the thatch and i over seeded the lawn last week and laid seed in the bare patches. This is how its looking at the mo.

[img]http://i.imgur.com/WCG3w42.jpg[/img]

The seed doesn't seem to be germinating yet but is this due to perhaps the soil not being warm enough? I put the sprinkler on the garden every evening now for 15 minutes as well. I sprinkled some top soil that i got from wicks over the patchy parts and used the back of the rake to gently mix the seed in.

Im kind of new to this but getting a real enjoyment out of it as well as frustration :-) If the seed doesn't germinate soon does it just die or can it be left?

Thanks everyone