What should I say to him?

My boyfriend hasnt been talking to me for the past couple days. we dont go to school together so when we talk its through texting. He hasnt texted me a lot and when he does it takes forever to text me back. Or he forgets about him untill i remind him. Yesterday on his break his called our friend brienna instead of me. We havent even talked on the phone for a couple weeks. When i asked him if anything was wrong he just said it was a long weeek but i dont think it is. He is drving me nuts and making me mad. Why wouldnt he call me?? should i mention something about her?