awkward silence vs comfortable silence

i’m the type of person who prefers comfortable silence over small talk (with people im quite close to) but how do i know whether it’s awkward or comfortable for the other person??

so i’ve been friends with A for a year and a half and i would say we’re kinda close but whenever our conversation ends and i just keep quiet she would go “hmm” audibly and it annoys me so much because i just get so worried that she thinks that i do not like her so i’ll feel pressured to just talk about random boring stuff.. and i dont know if it’s just me but i feel like it isn’t necessary to keep on starting a conversation with people i’m already quite close to?? is it wrong of me to think like this please tell me

and another case would be B, whom im friends with for about a year too. whenever i take the same bus as her or when i’m walking with her to our next class we’ll try to start conversations but after they end both of us remain quiet for a while, and for me i just assume she thinks the silence is comfortable so i don’t talk at all but what if she was just waiting for me to initiate the conversation?

i really do not know how other people’s minds work but should i always initiate a conversation when the previous one ends? any advice would be greatly appreciated