I was in the same boat an year ago with considerable thinning/miniaturization. First thing to do consult a dermatologist and also get blood work done to rule out any other possibilities like thyroid etc. Next thing is to do some reading on r/tressless subreddit. If it is indeed MPB, you need to jump on finasteride/propecia as soon as you can. Start with .25mg/day for a month and slowly increase dosage to 1mg/day over the course of a few months. It will take atleast 6 months to an