New lawn from seed
 

Hi all, I'm new to this forum so bare with me.
I've recently seeded a brand new lawn from scratch, roughly 12 weeks ago. All was well, lovely grass came through, gave it a cut. Few weeks later and my grass is full of clover and the grass has gone a yellow colour in patches.it seems like my grass is hardly growing but the clover is! It's driving me mad, I've read so many different things on what to put on it, but I'm worried it might destroy the grass altogether with it being young grass. Any recommendations? I'm new to gardening with just buying my 1st house. Thanks