Physical sign

Has anyone noticed that “hot flashes” are a sign for oncoming hypomania/mania? My boyfriend has some other potential symptoms I’ve been noticing, like tons of energy and sleeping for only about 4-5 hours at night (he generally needed more than that). He is also extra energetic and excited. He’s argumentative (tantrum-like) if I disagree with him or I want to do something not his way. Obviously, some of these are personality traits and the very up mood could be because he’s happier (on medications and things have been going well in our personal and business life). He was on Zoloft for several weeks alone but has been on a mood stabilizer with it for about a week. I thought I remembered reading somewhere about the strong feelings of body heat at the onsent of hypomania though. He has that, but, of course, he denies it’s anything.