Is it okay to always text her first?

The fact that you start the conversation tells you very little on its own. Some people are slower to text or find it awkward to open a chat, and they'll happily reply in full once a conversation exists. What matters is the shape of what she sends back. Count how many words she writes, whether she adds a question or a detail of her own, and whether she ever brings up something you didn't mention. A woman who is interested will usually add a little something, even when she's busy. A woman who isn't will answer exactly what you asked and stop there.

Also look at timing. A reply that comes back within a few hours and matches your energy is different from one that arrives the next afternoon with nothing extra in it. If she replies quickly but briefly, she may just be a low-effort texter who likes you enough to answer. If she's slow and brief, that's a clearer read on where things stand.

When you send a message, the most useful thing it can do is hand her something she can pick up without effort. That usually means a specific observation about something she said earlier, a small piece of your own day that invites a reaction, or a light opinion she can agree or disagree with. Each of these gives her a foothold. The message shouldn't ask her to come up with a new topic from nothing, and it shouldn't end in a way that makes silence the only available response.

Avoid messages that feel finished. If your text answers everything and asks nothing, she has no reason to write back beyond acknowledging it. Leave one thread loose, something she can tug on. Over several exchanges you'll be able to tell whether she starts pulling on those threads herself.

If she goes quiet after you send something, the most useful information is how long the silence lasts and what happens when it ends. A single day without a reply is normal and tells you almost nothing. Two or three days of quiet followed by a short reply is a pattern worth noticing. If you keep texting into that silence, each new message adds pressure without adding information.

A reasonable approach is to let the thread rest after a message that didn't get a real answer. If she comes back on her own, you have your answer: she's interested enough to start. If she doesn't come back after a few days, a single light message on a different topic is fine. If that also goes unanswered, let it go. Continuing to send past that point won't change her interest level. It just makes the lack of it harder to ignore.