Hello Friend, Good that you are seeking a help here. Regular and sound Sleep is important to Maintain both physical and mental health. If you are getting disturbed sleep and sadness , then it's could be a symptoms of depression or stress.. Advice you to take a professional help to assess your suitation and explore the reason or root cause

Feeling low, having crying spells, sleep and appetite disturbances, and difficulty in concentration and attention are some of the signs of Depression. Consult a Psychiatrist for a detailed assessment. It is likely with medication and counselings the symptoms will improve. If you are feeling suicidal or hopeless consult a Psychiatrist immediately.