First, I would say enjoy what you *do* have. For this kind of thing in my relationships, I feed on, "be content with such things as you have," in Hebrews 13:5. And for things like this, I have ways of evaluating, that I use for myself; but I am not you. So, below, I just offer, for you to test.
I think Christians need
to be accountable to each other. She is young; people who care for her should be included in the know about what is going on.
You have feelings for her. She is a young Christian. You do not know how she will become, later, as she grows in Jesus. So, she won't be the person you have feelings for, now. Plus, often enough, ones do not know who they marry . . . until after they have been married, for a while. Who you see her to be is who you now are able to see, as a person who needs to grow much more so you with God have much more reliable perception (Philippians 1:9, John 7:24). So, if you are capable of being guided by God, and He has not given you feedback that you know is from Him, trust Him on this. And if you have not become very good at knowing God's communication and guiding, this is what you really need to deal with.
And a friend, I'd say, is someone you can trust, by talking with him or her about this. So, if you are not comfortable sharing this with her, your friend, or her parents, or his parents, I'd say you need to grow more in your general relating with Christian people, so you can be more in communication and trusting accountability with others, in general, who are Christians.
But I have a prejudice behind this: if I get interested, for sure, in a lady, I intend to share this with my whole church, because we are Family. And if I get put off or out, by her, I also intend to share this, because we love each other and have trust. This is partly because I consider marriage in Jesus to be a Family blessing, and not just me isolated with one other person, but we all feed each other so we do well in our marriages. And we need our seniors and much more mature couples to feed us and guide us and help us learn how to relate in love, so we do well in marriage. So, I say isolating yourself, pretty much, with her would not be doing this. We need to feed on the examples of ones much more real in love than we are.
Plus, I think we can have our way of making too big of a deal out of one person we want to marry. We need to *humble* ourselves, not make such a big deal of ourselves and each other. And our more mature couples and seniors in Christ are more like Jesus than we are; so I'd suppose that, if we really do appreciate Jesus more than ourselves and each other, then we would appreciate our more mature Christian couples because they are more like Jesus, than we are
Your love with Jesus and more mature Christians can be so much more fulfilling, than what you can have with someone more your own level, even though you have much in common and are compatible. Jesus and more mature Christians can relate with you better, in love
helping you find out how to relate better with each other. So, I would not put too many emotional eggs into one basket, but invest in learning how to love with various brothers and sisters, and see how this effects your choice.