Is it normal to have feelings for a girl but have an amazing boyfriend

my sister is bisexual & she has a gay friend shes really cute but i have a boyfriend that ive been seeing for quiet some time now the gurl is about two years older my bestfriend asked her about me last night & she said all the right things like shes very pretty,athletic & outragously funny n outgoing things i havent heard in a while so sumone help me understand is it normal for me to like her