I think that's normal. I'm right-handed, but I have my phone in my left pocket and tend to use it in my left hand when using it with one hand. Last week I also had someone ask me whether I was left handed because I used my fork in my left hand to hold the food still and my knife in my right hand to cut the food. I honestly never think about these things, they just kinda happened over time because it worked for me. In my experience my dominant hand is obviously better for most things, but in the end it's also a matter of training. If, for whatever reason, I use my non-dominant hand for something repeatedly instead of my dominant hand then my non-dominant hand will get better. It's just that the dominant hand improves faster and has a higher "skill ceiling" in my experience.