What shall I do next?

[Helen]

You're probably coming on a little strong. You started trying to make conversation on two platforms a couple of days after she broke up with her boyfriend - that could come across as a bit pushy. Ofc she's gunna be upset after a break-up, and there's not much anyone can do about it, no matter how much you would like to.
Your attention probably makes her feel better and gives her a bit of an ego-boost, but that doesn't mean she has any feelings for you.
Personally, I think the best thing to do is leave her a message saying you hope she's ok and you're there is she wants to talk. Then leave it for a while. If she messages back, she's ready to talk. If not, maybe she'll come round or at least you won't be wasting your time. Sure, you might think you don;t care about your happiness right now, only hers, but it'd suck if you kept this up and she got with someone else.