Here it is, it's ahead by two I thought think https://mangas.in/manga/here-u-are
They didn’t really give much explanation, he was there getting tested for smth and he asked the nurse if they could hurry up bc he wanted to go home early. The nurse said sure but as soon as he gets home he needs to rest. He’s probably sick bc when he got home he said(to himself)that he doesn’t want Yuyang to see his “sick face” so that’s why he didn’t pay much attention to yuyang when he got home.

I have the raws in spanish if anyone wants them there ahead by some chapters not much tho