Sonogram, 1 healthy baby, 1 almost empty sac

Went in for 8w sonogram and there was 2 sacs 1 with a very healthy baby, the other with a white area, but no heartbeat. I have been SO sick. Doc said I’ve probably been sick because I had high hormone levels like for twins, but obviously one never formed. Called it a vanishing twin. Will I start to feel better once the other sac is absorbed? So happy with my one very healthy bean, but curious if I will start to improve?

Thanks!