Orgasm help!

So my ex would eat me out and I was able to cum, but it took awhile for me to get the hang of it. It just naturally came. Well, now I’m with my boyfriend that I’ve been with for 4 months now and I just can’t cum for some reason. Sometimes it feels like something is blocking it when I try to. I don’t know what to do. He gets extremely upset when he isnt able to make me and it makes me upset... what do I do?

EDIT: GIRLS HE MADE ME CUM! He was so excited and happy! It didn’t just come out, I squirted in his mouth lmaoo