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I'm a female-to-male transsexual (age 14), and generally consider myself to be straight. My best friend is a biological male who is 15 and also straight. Recently we've been fooling around with each other, even though it's really one-sided on his part. I've seen him naked before, and watched him masturbate. He doesn't seem to mind me being around, and he doesn't expect me to do anything in return because he knows I can't. I've touched his naked body before, but never his penis or anything else inappropriate. I am always clothed to some degree, but have been only in a shirt and boxers at times. He has seen me completely shirtless, but I don't consider that to be nudity or anything inappropriate because I am male, regardless of my biological sex.
We are such close friends we feel it is fine to break our sexual orientations with each other. He always tells me how male I am to him, has stood up for me before, won't out me to his other friends, and even talks about paying for my surgery when I'm old enough (don't know how he's gonna get the money for all of it though). I enjoy these encounters with him, but I still can't help questioning my sexuality because of them. I wouldn't mind discovering I'm bisexual or pansexual, but I'm not sure if I really am other than with him, my close friend. We usually act straight, and talk about hot girls we like, but we keep breaking our heterosexuality for each other as some sort of experimentation. Should I stop worrying about this being a challenge to my sexual orientation and just accept that he and I like this?