Genetics play an important role but as far as I understand you are more likely to inherit from your mother's side.
It is certainly possible you have started losing hair already, but at your age it could also be due to stress. Have any stressful events happened in the past 6 months? Usually hair loss because of stress comes with a 3-month delay. And it is reversible.
Just to exclude stress maybe you could wait a couple of months more to see if the situation worsens or improves.
Minoxidil doesn't have many side effects but sure it's a burden to apply it every single day. I recommend to not overdose on it because studies show you won't get better results but may seriously increase risk of side effects. So according to my dermatologist the recommended dosage is 2 x 1 ml per day, but if not 1 x 2 ml is OK.
Maybe it's personal but I don't like the sticky feeling of minoxidil. It's because of the propylenglycol. They say it's needed to help aborption. That's why I usually apply Monoxidil when I know I'm gonna wash my hair in 2-3 hours ahead, but I'm not sure if the product is fully absorbed by then.
Personally I wouldn't mess with your hormones (finasteride) at your age.