Need some help figuring out what i am... only serious answers please. ?

I am 15 years old. i have a boyfriend right now. and have had many throughout the years. but i have had a crush on this one girl for over a year. i just started seeing her again and now i like rly rly like her. i dont know if this means im bi or . or if its just a stage. should i try it out and see? i dont want no one to know though. because theyll think diff. of me. and i DEFF dont want my boyfriend finding out. but like.. she kissed me once. i liked it. am i bi? im okay if i am. i dont mind. but i am tired of questioning it. i want a real answer. please help. i really do like her...