Thinning of hair from the left crown only? Is this a form of MBP? (Photos)

Based on your description only it is difficult to diagnose exactly what is occurring but most likely this is Androgenetic Alopecia or Male Pattern Baldness.I would recommend a thorough evaluation by a Dermatologist or experienced Hair Restoration surgeon to develop an appropriate treatment plan for you.

That is not a hair loss because of ongoing process of androgenetic alopecia but  you have an experience of the simple juvenile type maturing of frontal hair line.  That is seen almost every young boys almost between 16-21 that have a very rounded hairline without recession in the corners.  Recession in the corners is a sign of mature pattern male frontal hair line.

I'd recommend switching to organic products for your shampoo and conditioner, and to look in to preventative medications like Finasteride and Minoxidil which has been proven to halt and even reverse hair loss.  PRP would also be an option for you. Before starting any medications it is best to check with your physician.

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 see a
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 to do
over the years to come.