Should i ask this girl out?

i got her number 2 days ago. it was the first time i talked to her. shes in my art appreciation class. the problem is i asked for her phone number for school purposes. i wanted to text her to chill for my bday on the 4th but idk if its too early to do tht. i told her i was going out of town so if she asks im just gonna say "o im going out of town next week not this week, i just wanted to get yur number" wat do u guys think i should say or do?