@BananaBandit To continue making progress, it's important to challenge your muscles by gradually increasing the intensity or variety of your exercises.
Additionally, your body type and genetics play a role in determining your potential for muscle growth. While you may not have the ideal foundation to turn yourself into Terrell Owens, focusing on proper form and gradually increasing the difficulty of your exercises can still lead to improvement and help you achieve your fitness goals.
You mentioned that you prefer to exercise on your own, and that's perfectly fine. You can consider incorporating other bodyweight exercises into your routine, such as pull-ups, dips, or squats, to target different muscle groups and keep your routine varied. It's also important to give your muscles time to rest and recover in between workout sessions.