my boyfriend and I just started having sex but whenever we do, he doesn't cum at all....I asked him about it and he just said " because I'm good like that" but when I continue asking he told me that it's not that easy for him to cum....I've never experienced this b4 so it's making me very uncomfortable....he also does not switch up positions when we have sex, could it be that he's just inexperienced or somn....wanted to see if anybody could shed some light on this for me?