She probably got busy or something or it's most likely that she didn't really want to say "No" again or continue with the conversation...
Your texting should've been more like:
You: Let's do something on mmmm... friday, I know this cool place that I'd want to check out and you'd probably be free on the end of the week.
The above shows you're "direct" and don't care if she declines and it would also give her options to reschedule too!
if she said she's got midterms, ask her more about that..
Eg:
Her: OMG, I'm so sorry but I really gotta focus on my midterm
You: Oh yeah, I hated studying for midterms
hehehe.. What are the subjects you got?
Her: Chemistry and Math, I know they're hard!
You: Yeah, when are they scheduled?
Her: I have one this friday and another next friday
and YOU stop it right there! She'll message you back if she's interested and I'm sure she'd indirectly hint you on a reschedule like "I'm free next Sunday".
You can't force her and broadcast to her that you really need to meet her like you did.
Show it to her and let her chase you
Follow that, that's the recipe 
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