Maybe there is something wrong with her right eye. If she wears contacts, contacts often lead to dry eye. Maybe she just feels that her right eye is very dry and want to moisten it through blinking. Or the muscles that control the movement of our eyes can't function well. I think if one has this symptom, he or she needs to see an eye doctor immediately.
Are you a boy? I think maybe she is flirting with you. You just can't understand her meaning immediately. But I also heard that if someone was hurt especially when their head was hurt, it often causes some uncontrolled twitching of muscles. Sometimes this may happen in our face. Sometimes it may affect other part of our body.