Am i gay? Please give me a honest opinion?

im a 15 year old kid and ive been going through something and its been making me sad because i dont know what i am anymore. Since about last October, I defined myself as straight and i probably can estimate that ive had around 30-40 legit crushes on girls before but, at that time i wasnt the most confident kid so i never dated any of them but i have had 2 girlfriends before but with girls i didnt have feelings for and didnt last very long. This year i enrolled into a all-boy and havent had much communications with girls. I've started to get really turned on my gay things especially porn and it drives me crazy because i want it to stop. Ive never had this type of arousal ever with straight/lesbian porn and that makes me mad as well because my friends claim they get really horny watching straight porn. Also ive also found men attractive which NEVER use to happen and had feelings that when i got too close to guys ive wanted to kiss them(mainly on the cheek) Ive had a sex therapist and he said that this was normal and didnt think i was gay but still im scared. Like i said ive still never had romantic feelings for guys like i have for girls. Could this be a phase?? or am i gay or bisexual