This approach will probably be hard for you, but I think it has the best chance at yielding the best results, regardless of the outcome (friendship/romance). Talk to her, mention to her that some of her behavior could be interpreted as romantic interest, and ask her if that was her intent. Treat her like a friend. With honesty and respect. If she says no, then you can just say 'ok, thanks. It was just confusing for me, so I had to get it off my chest and find out for sure'. No reasonable person is going to conclude with 'omg he was just trying to get in my pants all along'. If she says yes, then ask her out on a date (assuming you are attracted to her). Either way, your friendship is saved, and you get an answer.
And if you think you'll stumble in the conversation, practice speaking the major points to yourself first till you feel comfortable.
And if you think you'll stumble in the conversation, practice speaking the major points to yourself first till you feel comfortable.