What did i do ?

My SO and I are becoming very distant.. At least he's distant with me , I see him on other social media sites all the time but he just isn't talking to me, he hasn't in 3 weeks. I don't know what I did because I haven't done anything to him. I treated him like a king, took him out on his birthday, everything..

He told our mutual friend that im immature because I got nervous over something. Yet still he doesn't speak to me about the problem. And when our mutual talks to him about what he's doing, he just doesn't care. I sent him a text saying its over but he hasn't replied in weeks.. What did I do ? Does he just doesn't care?