questioning sexuality?¿

I have a boyfriend that I’ve been with for almost 2 years and I’m just so in love with him...but there are sometimes were I’ll see women and I’m just attracted but idk if it’s enough that it’s sexually orrrr? (Ik I like men so I feel my only thing could be is that I’m bi) me and him have even talked about having a threesome with another girl.

It was kind of my idea, I want to find a girl I can explore with but I’m soo awkward about things. And what if I’m not bi , she would hate me, wouldn’t she ?