Should I ask her to be my Valentine?

This girl and I are getting along well, but we aren't ready for a relationship yet. She has a pretty big crush on me, and I am definitely interested in her, but i still want to meet her a few times outside of school first. How serious would asking her to be my Valentine be? I want to make her happy, but i won't be able to get her a gift (maybe a sweet personalized gif animation, made from scratch, but not buy one) or do anything after school. so, basically, would it be ok to ask her to be my valentine to show that i'm interested, or would that just seem cheap if i can't do anything with/for her?