Ok, I been flirting with my waitress and she basically asked me to join her for a drink. Then I got her number, etc. Texted her once 2 days after the drink, went well, made jokes, call-back humor, etc. Texted her again 3 days later Sunday, she was again responsive and playful. Anyways, she seems to be showing ioi, I asked if she wants to join me and my friends for sushi and she said she has to work. So I suggested a drink after she gets off work, but she turned that down as well because she said she needs to catch up on school work, etc, and its late on a Sunday. But didn't suggest an alternate time. We texted a little after that and she said she promises that she'll let me buy her a drink. I'm fairly new so just curious if this is standard, and no reason to stop pursuing yet, and is there a better way to ask her out to get a more clear signal whether she wants to or not? PS: we ended the text convo just fine, no cliffhanger or unanswered texts or anything.