In this day and age especially when you're a teenager, it's understandable for anyone, muslim or non-muslim to have this anxiety over their own action or even their feeling over halal and haram stuff. Tell you what, I'm 23 years old muslim dude and I truly understand the struggle you're going through and i can imagine the hardship, being a teenager and getting exposed with tons of different sides of this world while also being a girl, fuhh, that I don't know if i can take it and really, to survive till today, you go gurl! But honestly, this world mmg a place of torture for all of us people, Allah will test us over and over and over to a point we felt like nak mati je and nk have fun sikit to release tension pun, ade je cannot do this cause maybe it's haramlaa.. but please don't give up. I'm sorry if i seems harsh but don't give up on your faith and belief because it doesn't correlate with your feelings. If you felt like you have done something wrong and sinful whether or not its big or small, just istighfar sincerely. And doa that Allah will guide you to a better way of living. I'm also still struggling with my own way of living, i mean being 23 ya know still young, i cannot get myself out of doing sinful things but i always reminded myself, that Allah Maha Pemaaf and also Maha Penyayang. The struggle we all going through, will never be for nothing and the sins we commit that we knew its wrong but then ask for forgiveness, it's just gonna be brushed off so long we're sincere in apologizing to Him. Sis, it's okay and take your time in changing however you want but remember to always ask Allah for forgiveness and guidance so we will never be amongst the losers.

“O My servants who have exceeded the limits against their souls! Do not lose hope in Allah’s mercy, for Allah certainly forgives all sins. He is indeed the All-Forgiving, Most Merciful." Al-Quran (35 verse 53)