Should I be concerned that one twin seems less active?

Courtney

I’m 20 weeks this week with girl di/di twins. I tend to feel Baby A more frequently than her sister. Is this a reason to be concerned? I have been having a ton of gas pain so I have been feeling less kicks overall as I pay more attention to the pain. I’m want to believe Baby B is just positioned in a way that I feel her less but I can’t stop worrying.