"are you really sure that child is mine?" He keeps on eyeing your still small belly as what you mention earlier to him you're still at 6 weeks of pregnancy, Jungkook was still trying to process what you just said to him as its all sudden.

He doesn't remember anything that happens before he gets super drunk at that party, it was also his first time meeting you so he doesn't see you as someone familiar

You just barge in his apartment and deliver the news of you being pregnant with his baby