Cum too soon

So I’ve been seeing this guy and we have sex like twice a week. And when we have sex, he gets too excited and cums in max 5 -10 seconds of penetration. I don’t know if something is wrong with me or with him or that’s how sex is. Im very confused as whole day he says he is aroused and he is always aroused by me but during sex he just kind of gets done too quickly. He says if Done more often resistance will build but I don’t know. Is there a way to make it last longer? Because he really gets turned on the whole day and I get into the mood the whole day and I get too aroused for him but it’s quite strange it ends in less than 5-10 seconds.