My girlfriend comments on other guys pictures

My girlfriend and i have been dating for a month now. Shes dating me yet she always comments on other guys pictures with emotions such as: "😍🔥" so basically she comments fire emotions, in love faces, and hearts. Im a jealous guy and she knows this already. It really bothers me when i see her do this. One time, me and her were talking about kim kardashian jokingly and i told her about how the porno is on the internet and she said "if you watch it i swear i will kill you" clearly because she doesnt want me to look at any other females like that except her. Moreover, i never comment on any other girls pictures and i just find what she is doing straight up disrespectful and stressful. Should i talk to her or am i overreacting and let it go?