How are kills counted in the game?

This may sound stupid but the reason I'm posting this is because in the previous game I was 100% sure I got a lot of kills because I was walking around picking up blueberries for at least 8 kills, when i went to the scoreboard after the match I found that I only killed 1 person and died 8 times!! Which made me doubt that the game is broken from the beginning, but I am sure that there is something I do not know. I did not leave the squad throughout the game and stayed in the same one, so this cannot happen. I was not sure of anything throughout Lately as I'm sure this is my performance, how is the kill system calculated?