I think a lot of people (probably the majority? but I don't know!) have sexual feelings towards same sex when they are young and first discovering their sexuality. I have no problem about this, I think it's a normal part of discovering your feelings etc. and growing up. Obviously, some people then mature to be gay or bi. But, I think it's a mistake to get too fixated on those feelings, because in fact many people who have this feeling when they are (relatively) young *aren't* gay or bi. Then, perhaps they have the thought, "oh, I am gay/bi", when really they are hetero. And there could be problems because of this, such as getting into a relationship that's not right for them, or other.
It's usual to find the same sex attractive to some extent anyway, I think partly it's a kind of 'discovery' thing, and also instinctive thing, because if you see beauty/attraction in someone the same sex, that is how you learn what is attractive. So, if I see a beautiful woman (btw I am not gay/bi), I get subconscious signal of 'what is attractive', which is one way to learn what is attractive to men. So then, maybe, I could try to imitate something of what makes her sexually attractive. Of course, I have never done this consciously, I am simply thinking a theory of 'why do many people feel attracted to same sex and then not go on to become gay/bi?'
Sorry, I have been rambling too much!

and not saying anything too helpful... But I would say to Thor, no offence meant to anyone but, maybe to wait a while before thinking 'I am definitely bi'...