My boyfriend is being off with me

Cerys
So recently I came home to my mum in Manchester and since I told my boyfriend I was going to see my mum he just turned around and said okay, bye then I know we were supposed to come down to see my mum closer to my 18th birthday but I couldn't wait and he didn't wasn't to stay for longer than a day never mind for 2 weeks so I came by myself but ever since I got home he's refusing to talk to me won't message me or pick up the phone he ignores my texts, messengers and snapchats and he said he will talk to me when I get back but I'm not coming home for another 11 days and he says he's not coming down to see me on my birthday , we spend a lot of time together and I just thought that maybe sometime away from each other would be good for us but I guess he doesn't feel the same, I don't want him to ignore me, but I don't know what I can say or do to make him talk to me 
Can anyone help me ???