I'm 20yrs old, using finasteride. Worried about side effects of muscle growth. Advice?

using finasteride 1mg Genisis for 9 months . I have no side effects maybe i have but didn't noticed that sexual coz m single. Night and morning errection normal. But m affraid of muscle growth.i ve heard that DHT can help in muscle building and vascularity while fin block it. So is it that free testosterone that help in muscle building or DHT as well. And if it block dht then the free test will increase and more will convert to estrogen or not?If they change to estrogen so it can have adverse effect? Should i take aromataze inhibitors?