Is this girl genuinely interested or just playing me online?

Ok, so I texted this girl I met online. We’ve been texting for about a week now. But last night something felt off. I texted her, it was a bit late 11:00pm. She enthusiastically responded within 2 minutes and asked how I was.

I replied the same way she did and asked how she was. It’s now afternoon and she hasn’t replied back.

I am starting to believe she has someone else as she turned on her do not disturb on iPhone since last night.
Is this girl genuinely interested or just playing me online?
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