Confused!!

So me and my boyfriend of 6 months decided to get busy in the bedroom tonight. On a good week, we do about 3 times a week. He went down on me like he always does to get me mine, because it's stupid hard for me to come during actual sex. But when I did, I felt like it took forever. I could feel it coming, it just wouldn't happen. But when it did, it was the best one I have had in a long time. Right after I started laughing, which I do sometimes, but I then immediately started crying. Which I've never done. He's so scared he done something wrong, although I keep telling him different. Please tell me I'm not the only one that this has happened too.. 😓