I started balding at 21, I am 36 today. Is it worth starting finasteride or hair loss treatments?

I suggest you visit a hair restoration doctor in your area. Your scalp examination will provide you with all the answers you need.Depending on your hair loss stage, medical therapy with finasteride, minoxidil and hair restoration surgery may help you.

It's not late to start some treatments like prp and mesotherapy ones. It can help to your hairs that still there but it won't solve the problem of hairs which have already fallen. The only way to get your hairs back is hair transplantation. the process is about taking your follicles (grefts) from your back which is donor area and transplant it to the bold part of your head. These hairs won't fall out again. It will stay with you.

Finasteride is scientifically proven to help prevent further hair loss. Sadly it's not for everyone. To treat hair loss, I believe it is always worth knowing what your options are.But that begins with gaining an understanding of the true cause of your hair loss. This is easily achieved with a consultation including a scalp assessment. In addition, you can have a test to identify medication(s) that are more likely to work for you.
With the underlying cause(s) identified, you may choose to take steps to prevent further hair loss and also work to maintain the hair you still have in terms of hair quantity and hair thickness or health.
Worth the fuss? Yes. Seek a dermatologist or hair specialist to help.