I had been through a depression which i think i overcame. however, the appetite loss and disturbed sleep (sleep too much, unusual timing) are still persistent. is that normal ?

Partial remission?: It doesn't sound as if your depressive illness is quite gone. See your primary care provider or mental health practitioner.

Depression: Depression manifests with five or more of the following symptoms, present most of the day nearly every day for a minimum of two consecutive weeks. ●Depressed mood* ●Loss of interest or pleasure in most or all activities* ●Insomnia or hypersomnia ●Change in appetite or weight ●Psychomotor retardation or agitation ●Low energy ●Poor concentration ●Thoughts of worthlessness or guilt ●Suicidal thought

Stay with treatment: Stay with treatment/therapy until you're sleeping and appetite improve. You may not need to see therapist or doctor as often; but stay connected for guidance. Many factors could be effecting your sleep and appetite, eg, stresses, SAD. See: https://secure02.kidshealth.org/teen/your_mind/mental_health/depression.html?tracking=T_RelatedArticle# Take good care of yourself. Best wishes.

Therapy?: Typically not. Have you yet tried any form of psychotherapy? Typically, the optimal combination of things to treat emotional issues such as depression is medication (which, on your best day, is supposed to take the edge off symptoms) but the real gruntwork takes place in psychotherapist's consulting room.