It's not happening quickly. This pregnancy part literally started when MC said he'd accept if he was empress and overlapped with other parts of the plot.
If you read the novel, it happened to quickly the end is near atleast 6-7 chapter left? I hope not
I really hope not
Except this Is Not the novel, it's an adaptation and adaptations usually skip some things or merge them together depending on the author's choices.
WHY IS IT HAPPENING SO QUICKLYYYY
PLS DONT END YET, I BEG ON MY KNEES.
I MAN I LOVE THAT THEY FINALLY GOT MARRIED. But hope it doesn't end where the baby is born.