My girlfriend was d about a month ago and we just found out she is pregnant and I need advice?

About a month ago my girlfriend was d and she didn't tell me about it till just now and She is pregnant! and I am forced into a place i don't know if I am ready for I haven't had with her and we were pretty close to getting engaged and now I just don't know what to do this was wrongly done to her and I want to stick by her and be there for her! But I have so many questions and no answers! I want to spend my life with this girl! and I want to have my children with her and I have to watch her have someone else's Child! She didn't deserve this and she is going through way to much right now and i can't burden her with my worries and concerns! I have never used this Q&A thing before but I have no one to talk to and everyone that has always given me good councle in the past I asked them for advice and they all said I have no idea and I know someone will know! Anyone who has encouragement or has ever had someone d that they loved, and they stood by their side i need some advice!