Relationship advice

Been with my boyfriend for just over a year now, recently he’s been acting strange he doesn’t call me or text me as much and when he does it’s just blunt responses. Sometimes he calls me and then 10 minutes later he’s fallen asleep after waiting the whole day for his attention he falls asleep on me. Even when we go out he seems off and not energetic as he usually is when we’re together.
Should I be worried? I’ve spoken to him about and he just says it’s nothing and I’m being paranoid. I feel like he’s lost interest in me or something.
What should I do? ...