Hi, Depression is a treatable condition. The outcome depends on many factors, the symptom severity, onset, duration, frequency, personality, social and genetic factors, also the mode of treatment and motivation for treatment. One can start seeing improvement within 15 days, but treatment usually lasts between 8 to 12 weeks, with additional booster sessions.
I hope I was able to answer your query.
Next Steps
Consult a Clinical Psychologist or a Psychiatrist for detailed evaluation and treatment plan.