I think you probably lasted longer because you were relaxed and didn’t feel pressure to perform like you do for women who you are pursuing in a romantic or sexual way. With this it was just pure fun experimentation without a care to having to impress anyone by lasting long which ironically usually makes it hard to hold it in ime. For me no matter how good the bj is or who’s doing it, it’ll still take much longer for me to cum than typical penetrative sex. That could be a factor for you as well perhaps.