be honest with you

this is not only common but also necessary. From what you showed here, you don't yet have teh ability to report the project to sr. managers. your colleague may have taken your credit, but it is fair to say you are not suitable for that position. If you want to make noise now, the ending for you won't be good. what you can do is to work with the other person, learn from her the skills and develop gradually. Be patient. frankly, sr. managers do not care who did the work. They only care the work is done. If you want to drop now, they have others to replace you, easily. don't ever think yourself is irreplacable. There is no such thing.