So there's this thing about some girls. Not everyone likes the attention boys have to give. Some girls are very closed and prefer being like that, on their own. So if you are continuously hitting on someone like that and she's not replying to you with the same enthusiasm as yours, it's pretty much likely that she's NOT interested in you. And you continuing to keep doing that isn't gonna increase your chances by any means, instead it'll just keep creeping her out more.
Simple things to look out for:
If she's interested in you, she won't be replying to you in one word or two.
If she's not coming in your posts on her own to start a conversation, she isn't interested. So don't do that shit in her posts.
You constantly going after her might seem a little fun to you, but trust me, it creeps her out.
Bottom line: Stay in your limits and don't be a nuisance. Yaha pe likhne aaye ho na, toh likho chupchap, logo ko pareshaan mat karo.