my boyfriend (19M) told me (19F) im not engaged during sex ?

My boyfriend (19M) and I (19F) have been dating for about seven months. He very clearly has a much higher sex drive than I do and has recently been wanting more sexual favours, and I'm totally happy to oblige and give him what he wants, but I need to be in the proper mood, or I can't fully get into it, I suppose, but that's brought up some issues since sometimes he does just want things without giving me anything in return or without trying to get me in the mood, which is fine, I guess, but it does take me a little bit to get into the proper place I need to be in on my own than if I had some help.

In this particular situation, he told me I'm not very engaging during those sexual interactions (blowjobs mostly), and he's told me I'm supposed to fake some of it when giving blowjobs, which I hate doing. I hate faking things, but in that situation I was on my period; I have extremely painful cramps, and just overall my periods aren't a great experience, but I still tried to please him how he wanted me to.

He's the first guy I've genuinely enjoyed sex with, and I haven't felt dirty and gross after. I enjoy doing sexual things with him, but recently he's just been a little more demanding, and I'd love to meet his demands, but I don't know how.

I'm just not sure how to be more engaging and what I'm supposed to be faking, if at all.

I asked him at the time, but he never gave me a clear answer.