|NO not your fault, no he's not in a hurry.
Men, especially younger men have very little control over their sexual duration. There is nothing you can take responsibility for here. However and Raven mentioned this is a behavior that has to be trained out of a man and if you want satisfaction you'll have to help him in this training. Discuss this problem with him out of bed in a very frank and open-minded manner. Explain your needs and your willingness to help in getting them resolved. Read up on the topic of ejaculation and sexual endurance. Work with him to increase his stamina.