Though I'm virgin, few days ago I noticed that my nipples are milking... I'm very depressed about it. Please help me.

You might want to consider visiting a doctor... To rule out anything bad, and find out what might be the cause.

No need to be depressed. While not necessarily common, it is not uncommon either. As smoothy said, see your doctor. It may be something as simple as a hormone imbalance, such as elevated prolactin.