Young and Confused

I'm 14 turning 15 soon and in the past year I've started to question my sexuality. I'm not sure if I'm Bi or Gay but I'm starting to gain interest in guys. the problem is I'm not sure if this is just a phase or something or if I'm actually bi/gay. So although i want to tell someone I'm scared to because of the fact I'm not sure. Is there a chance its just a phase or something?