Boyfriend can't cum....

so I've been gone 3 few weeks and everytime I come to vist we obviously have sex and....... he can't cum. He has no problems cumming, especially not with me before ... I can get him to cum by jerking him off and sucking him off but have no luck with sex anymore and it's definitely not boring sex ..& he moans etc but won't finish so I'm pretty sad about it. I'm just confused ..because when I was staying with him I was always there so he never really needed to watch porn.. maybe him watching porn turned him away from me ??

I've been with him for some time and I'm pregnant with his child so I'd hope he wouldn't cheat but I'm just at loss ... Advice or a possible reason.. obviously it's best to talk to him but I'm just embarrassed at this point.

Maybe I'm not good enough anymore

(There was no horrible reason I was away btw we were living together then covid happened and I decided to live with parents bc we both lost our jobs.. oh and he doesn't treat me any different and nothing has seemed off)

And he's not nervous to have sex with me bc I'm 15 weeks almost and he's pounded me when I was last here with no problem sorry lol tmi