The dates felt promising. You enjoyed each other's company, wanted to be close and thought sex might be another step toward a relationship. Then his calls slowed and the effort disappeared.
That change can hurt without meaning that your body, personality or decision to have sex was the problem. There are several possible explanations, and guessing at them won't always give you an answer.
First, be honest about what you wanted
Some people enjoy sex without expecting a relationship. For others, physical intimacy brings attachment and hopes for a future together.
Ask yourself whether you were comfortable with the arrangement you actually had. Would you have chosen it if you knew things might go no further? Did you want sex, or feel afraid that saying no would cost you the connection?
You don't need to criticize yourself for the answers. They can help you decide what feels right next time.
Three possibilities to consider
1. You wanted different relationships
He may have wanted a sexual connection while you hoped for an ongoing partnership. If he led you to expect more, the disappointment also involves how he communicated his intentions.
You can't establish his motives simply because he withdrew. If you want clarity, you can ask directly what changed and what he wants now. He may not give you an honest or satisfying answer.
2. Attraction developed faster than closeness
Chemistry can make someone feel familiar before you know much about their values, habits or way of treating people.
Look at the time you shared outside sex. Were you getting to know each other, enjoying ordinary activities and making room for conversation? If the connection centered almost entirely on attraction, there may have been less underneath it than you hoped.
Having sex early doesn't prevent a relationship from developing, and waiting doesn't guarantee one. The useful question is what you're building together.
3. He doesn't see the compatibility he wants
Sometimes one person doesn't want to continue a relationship that the other felt hopeful about. That can be painful without making their preferences an objective assessment of your worth.
You don't need to reinvent yourself around requirements he hasn't explained. Consider whether his way of handling the situation is something you want in a partner, too.
Choose boundaries you can feel comfortable with
If casual sex doesn't suit you, you can wait for more trust, choose celibacy or decide that a particular relationship isn't right for intimacy. The pace belongs to you.
Pay attention to how someone responds. Respect means accepting a limit without guilt or pressure. Notice whether care and interest continue when sex isn't part of the plan.
Waiting still can't remove every risk. A person may seem invested and later prove unreliable. Trusting someone who misled you doesn't make you foolish.
If he has already pulled away, look at what you need now: a clear conversation, some distance or support from a friend. You can reflect on your choices while leaving responsibility for his behavior with him.