How to respond to a 'lol' in text from a girl?

I know normally that this is a clear sign from a girl that she is bored with the text, I know people will bring that up, but I get it. Also, I did ask her out, but she said she would like to just text for a week or two because she barely knows me and had a super bad experiance with a guy she hardly knew- which I get, but it's hard to keep it going with someone I barely know...

Anyway, the difference here from most similar situations, is that we have been texting non-stop for over a week now, at least every 30 min if not constantly at night. We also both send huge long texts, like paragraphs long. So nothing had changed, we had both been texting long and quick as normal, but the last text I got was just 'lol'. Granted I did not really ask a question and could have just kept going with what we were saying, but I didn't want to force it or seem clingy- so I just let it go and now we are in an awkward silence...

A female friend said sometimes girls do something like that to see how interested the guy is (if he keeps trying)?

I have never enjoyed texting a girl so much and would really like to keep this going until we can meet up, at least to give it a chance in person. I will likely text her tomorrow anyway, but what do you all think?
How to respond to a 'lol' in text from a girl?
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