I dont know why you are taking 0,5 mg Finasteride, 1 mg is usually the recommended dosage, I dont think that or Minoxidil will cause permanent shedding like someone above suggests, and you will need to take it for a few months before seeing results, you can see some extra shedding in the beginning, I for instance noticed some extra shedding now after beginning on Minoxidil again which I hadnt taken for a few months, but since I have been taking Minoxidil on and off for several years I know this hairs come back stronger than before so dont stop using Finasteride and Minoxidil, give it time and you will see the results (that is in most cases, some people it will not do anything for but for most it will at least stop or slow dramatically down the hair loss).
In regards to Steroids, they can definitely trigger more hair loss but since you haven't been taking them for two years I hardly think they are effecting you.
The pattern isn't a usual one according to the Norwood scale but dont worry about that, not all follow this pattern.
I hope this works out for you and you get your hair to its former glory.