Is this a side effect of Finasteride?

It all began in middle of july when my excessive shedding started.my scalp got really flaky, itchy, oily and inflammed. I started taking finasteride on 18th August. The shedding continued for a week after fin.I shaved of my head, cleaned my scalp by removing the flakes and now have regrown my hairs to a good length. But now my shedding had drastically reduced.Also the inflammation and itch has gone.Was it the effect of finasteride on MPB or was it scalp psoriasis. I am in a big dilemma.