Is it possible that I could start Finasteride too early?

I suggest seeing a hair loss expert now to evaluate and go over your condition and provide you information about your best treatment options. There are great non-invasive options like prp/progesterone and/or hair transplantation. See an expert. Best, Dr. Emer

Something to keep in mind is that the large majority of patients who take Finasteride don't report any side effects, and of those that do, virtually all of those side effects go away when they stop taking it. In general I'd recommend against starting it unless you are beginning to see your hair thin, but being observant and checking your hair means you would be able to start taking it as soon as your hair loss starts. Taking a half dose does decrease the severity/likelihood of side effects, but it also would decrease it's effect of stopping hair loss. 

I don't recommend you to use finasteride . it is very early for you and ıf you have AGA , you have to use for life time to keep your hair on scalp!You may have Post-finasteride syndrome, occurs in men who’ve taken finasteride to treat hair loss by a chance of %4-5. That may causes some symptoms include: loss of libido, erectile dysfunction, depression, suicidal ideation, anxiety, panic attacks, Peyronie’s disease, penile shrinkage, gynecomastia, muscle atrophy, cognitive impairment, insomnia, severely dry skin and tinnitus. The condition often has a life-altering impact on victims and their families, such as job loss and the breakup of marriages and romantic relationships..

In the majority of people, Finasteride can help stabilize or prevent further hair loss. In a lesser percentage of people, Finasteride can potentially help reverse miniaturization. Please note that everyone has a different response/success rate with this medication. Given your strong family history, I think it would be reasonable to start Finasteride or start it early on in the miniaturization process. I recommend meeting with a hair specialist for a proper scalp exam. 

The earlier that you start the drug finasteride the quicker you will see a response. Hair that is lost while you are not on the drug may not come back.