Boyfriend....sorry if this is stupid

So me and my bf agreed yesterday we’d meet halfway so I can come home and whatever cause I’ve been at my parents for a few days I was borrowing my moms car yesterday and I thought oh maybe I can drive to my moms work and drop her car off so she has it and then we’ll meet there and he can pick me up and we’ll go home my moms work is so close to his parents house we live with his parents. He agreed and then it gets later and later I ask him are we still meeting up and he goes oh sorry I forgot and we started fighting because of it would you guys be mad too or am I overreacting I’m also 6 months pregnant if that changes anything... I just don’t get how you forget about your pregnant gf that sounds so fucked up. Sorry if this is dumb but my sisters husband is always there when she needs him to come get her if she doesn’t have her car. He then said today oh my grandma wants to see you and I told him I didn’t want to go because I was mad at him he said that’s fucked up she’s expecting you and I told him I didn’t call her up and say oh I’m gonna come see you and I told him what he did yesterday was fucked up and he doesn’t think so