I'm an 18-year-old woman, and I feel like my boyfriend, who is 31, hates me. Can anyone offer some advice?

I've been seeing this guy for about two months, and everything was going wonderfully until recently. Lately, he seems a bit distant and less affectionate than he used to be. I'm starting to wonder if I've done something to change how he feels or if his feelings were genuine from the beginning. He is still the same incredible person, but the warmth and love that he used to show me has diminished, and it makes me feel sad because I crave that connection. I'm eager to find ways to improve our relationship. I'd like to communicate with him about this, but I could really use some advice. Any suggestions on how to approach this or what I could do to make things better?