I miss my orgasms!

My fiance and I had started to get into a sex routine so I decided to spice things up with new lingerie, sexting, and a vanilla bondage kit. We've been having daily, amazing sex, and I've gotten so much better at giving him head, he's told me and it's just obvious because I'm putting more effort into it. Anyway, our old routine sex we'd always do oral, and he'd ALWAYS give me at least one orgasm, usually 3. Nowadays, he barely spends enough time down there to get me there, so I've just been giving up on getting mine and bending over and demanding he hit it from behind. He really enjoys it, my pregnant belly doesn't get in the way and he loves ass so it's a win win position for him. but it hits my cervix and while it feels good, it also hurts. I just try to make the best of it until he gets off because, by then, I'm exhausted from trying so hard to get off before he gives up on going down on me. What are some exact phrases I could say to let him know that I want him to spend more time giving head, since I am too, so that I can get off like I used to? I don't want to hurt his feelings and he thinks I did get off so if he knew I "faked it" (pretended I got off but really I just got really tired and got wetter, so that's why he thinks I got off is he thinks the extra natural lube was female cum) he'd be pissed. Suggestions on what to say to get him more interested in giving me multiple orgasms like he used to?