Your hairline is very similar to my own, and I believe its a NW2, some might call it a NW1.5, but at the end of the day it doesn't make a whole lot of difference.
The main point is that, yes there is a slight recession, its no longer a clean NW1, if it were NW1 the hairline would go straight across and not slope slightly upwards at the corners.
no one can know how far and how fast it will recede or if your hair is going to still more or less this way for several years. I personally doubt you have aggressive hairloss and you ll probably retain most of your hair until your 40s, at worst you ll become a NW3 by 40.
Its your choice if you want to try medication, would you prefer not risking med side effects (supposedly side effects are mild and not a big deal for most guys), or would prefer to better the odds that you ll keep most of your hair?