My (17M) gf (16M) sends selfies to her male bsf.

For context we are together for 5 months now. Yesterday we were out on a date and i randomly checked her snapchat. I opened the saved photos section and i saw she has been sending selfies of her and fit checks to her male bsf (16M). I had assumed that those selfies were only sent to me but i was wrong. I didn’t react at that moment because i didn’t want to ruin the date but it just made me feel insecure. I knew she had a male bsf she had known since childhood. But i didn’t know she was this close to him. My overthinking is driving me crazy rn. I wanna know is this normal among girls?

Edit: 16f hai guys