13 month old and just found out I'm pregnant

I'm posting anonymous because I don't want the judgment or belittling. Im married and have a 13 month old, this little boy is my world. I just found out the we are pregnant and I honestly am super upset. I'm not sure that I want another one. We weren't trying by any means it just happened and now I honestly feel so lost. I know it should be a happy moment but I was really ok with only having one at least for another year.. maybe.. if we decided on another.. My son is fun and a little more independent to where we can all do things and i started to get my life back. Plus the bond I have with my little guy im so afraid ill lose with having another one. Were not exactly in the best place financially for another little one and I dont think its a good idea at this time and I really am afraid of my little guy feeling like he's being replaced..I know it sounds irrational im just all over the place. A part of me wants him to have a sibling close in age and watch them grow and bond together but the other half is really just happy with how my life is right now. I guess I'm just wondering if anyone else has ever felt like this.