I had a colleague who was diagnosed with a burn-out. But a major part of it was his low iron levels in blood. A lot of psychological issues come down to physical ones and vice versa.
Sometimes just drinking more water can solve the shitty mood you had for weeks.
It is not always the case, but before self diagnosing yourself with psychiatric diagnoses, try to adjust your lifestyle. Eat better, sleep more, exercise. Have a doctor checkup and a blood work done.