A co-worker that I'm not sure that likes me or not..?

Well I've known her for a couple of weeks now. I've talked to her here and there and each time I take a glance at her, she smiles at me. I really don't know what to think of, you know? Anyways, I was talking to her the other day and asked if she's ever been to Disneyland (of course everyone has heh).. and after that whole discussion I asked if she'd want to go (not asking her on a date) she said no, then nervously said yeah she would like to go (at this point she could possibly be hinting that she wants me to ask her??) What should I do?? Just to let you all know I'm the nervous type -_- Please help!