Christian background + my best friend kissed me. Struggling

I have been great friends with this girl for about a year. We get on so well, seeing each other pretty much every day at uni, plus many hours of late night chats and catchups, or talking on the phone for hours. We were pretty cuddly and would just chill in bed and hold hands and talk - I didn't reaaally think a lot of it, or at least I convinced myself it was nothing...but this felt natural and I didn't feel conflicted. One night, about 6 weeks ago, she asked me if she could kiss me. It took such immense courage and she said she had had a crush on me for ages. We kissed for ages and it was the most beautiful and difficult thing all at once. For days after my stomach churned and I felt pretty sick. While all her friends knew about the situation (flatties etc), I felt like most of mine I couldn't tell...that they would not understand (some Christian friends who have more clear-cut/conservative ideas, although they are lovely! (bar a few gems!) My background is Christian - my faith (in a personal loving God) is a really important part of me, yet the tradition carries a lot of strong ideas about what actions are good/bad etc (esp with sexuality) that I don't truely subscribe to (/find hard to reconcile with my understanding of God)- I don't believe it's that simple that being with a girl is right or wrong...luckily my family also acknowledge the nuance and complexity of life...but I still can't tell my parents! but this is definitely something that I didn't envisage for my life and it's an absolute mind f***. This was my first kiss, which makes me completely shocked at myself. But I LOVE this girl. It feels like a really healing relationship in many ways (she is so loving and wonderful), and all my other crushes have been on completely inappropriate guys (me trying to "save" lost guys!). But I'm really struggling with the influence of culture/nurture on our perspectives. My friend is not Christian from pretty opposite family culture - some key similarities of love/kindness etc, but from this fairly hippy, random (and wonderfully inclusive) family. For her (with many gay family members etc) it's just clear that if I love her, it shouldn't matter on the gender...for me, I have a huge amount of internal conflict and I can't tell if it's my background/friend circle that is making me feel guilty/unsure about this, or if it's not going to be good, but I'm also terrified of giving this a go and then hurting her by backing out. I feel like she is already hurt with the way I'm acting when I'm conflicted. I feel really trapped. I feel kind of like my gut is screaming that this isn't a good plan, and yet my heart literally aches with missing her (it's summer holidays)! I Is this going to be ultimately loving/helping or hurting us both? Anyone with similar experiences? Cheers fam.

Thanks SUSIEDQQ, I'll take this on board!! <3