First off congratulations, that is quite an achievement!

If you want muscle definition you can do things like calisthenics or else you’ll have to invest in weights and weightlifting equipment. Those are really expensive though. If you don’t have the space or money to buy it then seriously reconsider using a gym. If I remember correctly from a previous post, you said you’re antisocial? If that’s correct I used to have the same mentality as you. “I’ll just workout out at home and be alone”. Doing this never did much for me. As of today, I consider going to the gym an antisocial activity. Once the headphones are in, the world is off. I’ve worked out in college gyms with frat guys, military gyms, corporate gyms,, and MMA gyms. No matter the environment people are doing their own thing and aren’t paying any attention to anyone else. It’s also a big motivator to workout hard because working out at home, I always half ass my workouts. Let me know if you have any questions about cardio or anything else.