Smiley face on my Timmy cups?!?

I go to this tim Hortons almost every day. There's this girl that been there for almost ad long as I can remember. She is 8 years younger than me. Until recently she's been super shy, won't say a word to anyone. Recently though she's started smiling at me. Then last time I got coffee, she drew a little smiley face on my cup and smiled at me. Then I was in there again tonight, she again smiles at me, and drew a smiley face on my cup again. She said something about a smiley face, but I didn't quite hear it. Does this mean I should try and ask her out? I feel a little weird being 7-8 years older than her. I'm 29. What should I do?