I can not breath OMG

I can't breath well at all OMG . My ob says laying on my left side will give me all the support I need but it literally feelings like I'm cutting off all of my oxygen, &I keep finding myself telling her shit she always fucking brushes off like its not an issue for me ... I can't lay on my stomach my back or my sides and I'm only 25weeks . I'm really small. I sleep with my head on my headboard with a pillow under my arm so that way I'm able to breath, but that it starting to make my back side and neck hurt. OMG I feel like I'm dying ... I can't be the only who who's had this problem 😔😔😔😔😔😔😔😔😔what can I do, I need serious help I'm losing my mind.