Most likely you are going bald. It happens quite young for some men.
You need to get male pattern baldness from your symptoms. Other causes may be improper diet, chronic illness, hormonal imbalance, infection, extreme exposure to sunlight, application of chemicals over scalp for hairstyling, bleaching, work stress and certain medication. Male pattern baldness is usually an inherited trait and men start lossing hair at an early age leading to extensive baldnesss. Since the nutritional deficiency is also a common cause of hairloss, patient is required to take food rich in protien,vitamins(mainly vit A and vit C) and other micronutrient like zinc,iron and copper.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.