Hair loss from the crown and thinning at 18! (Photos)

You appear to have androgenetic alopecia, or male pattern hair loss. It is not uncommon to see this starting at your age.
Your best strategy at this point is to take steps to keep the hair you have, as well as thicken your existing hairs. The treatments with the best evidence and efficacy include:
1. Finasteride/Propecia.2. Minoxidil.3. Low level laser therapy, such as a laser cap. A good laser cap will have 250 or more laser diodes only without any LED diodes.4. PRP (platelet-rich plasma).
If your goal is to regrow your hair, I generally recommend a combination of the above treatments. You can use any of them and all of them in combination with one another.

For start you can go with prp and mesotherapy treatments. In a mesotherapy session, the doctors inject a special solution into the patient's scalp, in PRP they inject processed blood. For optimal results, you will need 5 – 8 mesotherapy sessions, on the other hand, PRP will require 7 – 10 sessions. But in future you will need a hair transplantation to cover up your crown.

I strongly suggest you schedule a consultation with an experienced surgeon near you. He shall diagnose your condition and offer you a viable, realistic long-term treatment planAt this point, medical treatment would seem the best way to prevent further hair loss. Minoxidil and finasteride are effective medications against hair loss. Either of these components or both in conjunction can slow down further hair loss and even encourage hair regrowth in some cases. I advise staying on medical treatments for a few years before considering a hair transplant.After a few years, you will have a better idea of how your hair loss is progressing and you can make a more informed decision about surgical restoration.