Feel like I’m getting boring

When I first got w my bf (we’ve only been together 6 months) . I lost my Virginity to him I’m 18 . He used to cum quicker maybe in 5-10 mins & now he takes longer like he can go 15-20 or more without cumming & he said notice how I can last longer without cumming now & I said yea wat have u been doing jokingly. He said yea I’m just use to it now it ain’t nun.. so me ofc I’m like woah & he said wat u feel a way? Anyway I’m gonna go play fortnite which makes me think he isn’t satisfied or he’s just getting tired of the same old same . He noticed my expression changed but he didn’t care or try to reassure me like it’s still good so I’m kinda just laying here offended. Do I have a right to feel this way? How would you guys react ? Isn’t a few months a little to early to be getting tired ☹️