Husband not wanting to go down

My husband and I got married in January. We dated long distance for over a year and I moved to his state with my 9 year old. He is 29 years old and I am 32. I’m almost 33 weeks pregnant and have an almost 9 month old.

He has never been one to go down on me often even when we were just dating. He did it with more frequency than now with us being married and sleeping in the same bed. It takes me a while to finish and I think he considers it a job for him. He hasn’t went down on me since the end of May. My birthday was at the end of August and I asked him for that for my birthday and he didn’t say no, he just still has yet to do it. I ask him if something is wrong with me or if he just does not like to do it, and he says he is busy and tired and he has to schedule out 45 minutes to do that. It makes me sad that he doesn’t want to do it on his own. It is the easiest way for me to orgasm, as sex has only made me orgasm 3 times.

I’ve already told him I’m not going to give him blowjobs. He seems unaffected by it. We have sex maybe once a week if not every other.

I’ve never had to deal with this in a relationship before and I’m not sure what to do. Being pregnant my libido is on overdrive but he doesn’t seem that interested. Is it because I’m pregnant? I’m really at a loss here...