Hair fall and not growing back after shaving my head. (Photo)

I can't tell what you have as the cause of your hair loss without seeing your scalp up close myself and knowing all your details. You'll want to see a physician who specializes in hair loss - especially to rule out type IIIa male pattern alopecia. Blood tests may also be appropriate but again it depends entirely in your full story (which I don't have).

Your biggest enemy is the progressive thinning leading to a balding pattern that is not evident at this point in time. The degree of thinning that you are experiencing would suggest that you should seea doctor who most likely will get Bulk Measurements of your hair to determine the degree of the thinning that you are presently having. If the diagnosis is early genetic hair loss (the most common cause of hair loss in young men), then the best treatment would be the drug finasteride which is highly effective in men of your age and may not only stop the hair loss but possibly reverse it. If you are developing a more advanced balding pattern the best test to get will determine the Bulk Measurements of your hair and this will show, over a one-year time frame, how effective the treatment will be. Once you know this information, then you and your doctor need to develop a MASTER PLAN which will define what you need