Was my reaction wrong?

Me and my boyfriend have been dating for 2 months and a couple days, but we dated for 4 months before then broke up and got back together...Anyways he posted a photo on facebook saying comment your name and If I reply I fwy and If I don't the I don't fwy (F*ck with you). This girl commented and then I commented after her. The she replied to my comment and said, and I qoute, "U da girlfriend right?". I got really mad and told him to delete her comment abd he hung up the phone on me...Did I react the wrong way?