Sufcfed, I am in the same position as you. Judging by your picture, I have the exact same amount of loss as you and i style my hair the same way to hide the receeding in the corners. I went for a HT consult when i was 19, the doc told me i was too young to even consider a HT so he put me on propecia, rogaine nizoral.
I took the propecia for a month and found to have a difficult time getting an erection, so i stopped taking it. Fast forward a year and decided my hair was a priority and started taking it again. Only this time without side effects. I think the first time i was on it, it was more a psychological thing that was giving me a hard time with erection problems then the actual medication. In my head, i was expecting to have a hard time getting an erection which made me nervous about not being able to get one which decreased my confidence, which in turn made me unable to get one.
Today i am 21 and have been on propecia for about 1.5 years and have NO side effects at all. I have not regrown any hair but i can say i havent lost any more either. My situation is pretty stable as my hairline ends on a beauty mark on my scalp so i can tell it hasnt really moved.
In sum, dont worry about the side effects. It is probably a psychological thing in most cases, if you get what i mean