It's not uncommon to have some level of asymmetry in muscle development. Factors such as genetics, dominant hand usage, and previous injuries can contribute to differences in muscle growth between the left and right sides of the body. If you've noticed that your left bicep has grown a little while your right bicep has seemingly reduced in size, it could be due to a variety of reasons. It's important to keep in mind that muscle growth takes time and consistency. Results may not be immediately visible after just a few workouts. And make sure you're using correct form and technique while performing exercises to effectively target the muscles you intend to work. You can use
https://homegym-exercises.com/biceps_exercises_workouts.html for proper technique. Engage your biceps throughout the entire range of motion and avoid relying on momentum or swinging motions.