I am also a PhD student, but with a stutter. 1) When I experience negative emotions I usually withdraw and watch tv/netflix, or scroll on reddit. But aside the technologies, only sleep makes me feel better. 2) I use them every time after any situations in which I stuttered and felt stupid. 3) Not effective. As I said before, only sleeping really makes me feel somewhat better. Edited: I kind of have a persistent depression due to my stutter.