Cold approached a girl in a coffee shop

I met this girl in a coffee shop and the conversation was short and pretty casual. She gave me her number without me asking her! I felt good about her giving me the number, so I texted her the same day and she didn't reply till 3 days afterward. I made a mistake by deleting her phone number, I assumed she is not interested in me. Anyway, I received a 2nd text from her and again she didn't reply back. I'm a bit confused! How can I fix this , also should I call her and maybe skip the texting part..?