Hi, HotPotato2009!
Concerning a mid-life crisis, I would think that age 30 would still be a bit young for that to be happening. I went through mine from about ages 40 - 45.
Is there anything happening currently in his life that might be causing him to have stress? Also, does this sort of thing between you and him happen frequently, as far as the mood changes are concerned, please?
Hopefully, others will also come along to address your question.
Thanks!