Mayi,
I experienced certain pattern from my bf too. At first, I cannot tahan.
My bf's pattern since young is to hide in his room when he's super stressed! Even his mum told me that he likes to stay in his room whole day LOL.
Last time when he was super stressed with exams and work, he sometimes told me that he would talk to me later when I called him. As an impatient and fragile gal, I tend to feel sad that he was ignoring me!
After 3 times of such pattern, I can take it easy now, bochap him when he wants to be alone. When he's fine after 1-2 hours, he will call me back.