fiancé doesn’t want any nsfw stuff all of a sudden (21f.27m)

okay so without getting too in detail about stuff after our last visit irl my fiancé has completely shut down or rejected any nsfw stuff such a pics or conversations about nsfw stuff saying now it’s “gross” and “cringe” after almost a year of having that kinda interaction (which in the past was mainly initiated by him on an almost daily basis), he hasn’t stated any reasoning behind this sudden change and it’s left me feeling a bit off.. i can’t explain what exactly it is i’m feeling, it’s its rejection or insecurity or maybe both? i don’t mind him not wanting to but the sudden shift has left me wondering whats wrong. he also mentioned that he wants our sec life to change almost entirely the next time he’s here and that he did not enjoy the last time we had sex but didn’t tell me till 4 months after it happened, it was brought up completely out of the blue as well during a normal conversation.. any advice on how to get over how i’m feeling or just what might be going on with him?