he came but didn't feel it happen to him??

hey guys. So last night I had sex and when we stopped I tasted his cum on his dick. It wasn't until I pointed it out and noticed that his cum was dripping out of me that I realized he had came. During sex, he didn't feel himself cum. But afterwards he felt like he does after he cums. I was just wodnering if anyone's partner has had this happen to him before or if there's a reason for why he didn't feel himself finish like he normally does?