Girls: opinions on this situation?

I would say that she likes you a lot and you have done very well not to rush at her and to gain her confidence and make her smile warmly at you. I think you have judged her very well by your own feelings and I hope that you have the courage to carry on this quiet relationship and it could turn into something good. But don't be too reticent - try asking her out for a coffee or something after work and keep that eye contact going. Good luck.