I think I might like girls?

So I'm 18, and have always been adament and sure of the fact that I'm straight. I've always made jokes to my friends say how I wanna be gay, but I've never actually been attracted to girls..'I've kissed them on nights out when I've been very drunk but never actually felt anything. But last night I met this girl who was so cool and cute and I think I really did like her.. like I wanted to kiss her so bad and I did.. and it was so nice.. I mean it could just be the alcohol but even now I'm wishing she was in bed with me.. surely if I was bi I would've had these feelings before? Or maybe I just never met the right girls.. do is this normal to suddenly develop these feelings??