Pregnant how to cope

I just found out I’m about 5 weeks pregnant. I’ve always said if I got pregnant at this time I’d get an abortion as I wanted my son to be an only child but now I’m having mixed emotions. My son is 3 and he is my life, he’s spoiled pretty bad and that’s my fault but he doesn’t like when other kids even come near me so I’m afraid he won’t like being a big brother. I’m so scared. I cried all night because I know how I felt being an older sister and having to take care of my sibling all the time and my mother showing favoritism. I’m just so scared my son will feel the same way. I’m also afraid if I keep this baby that I won’t be able to spoil my son the way I do. I’ve always said I would never have another child because I wanted to give my son anything and everything he wants because I never got anything I wanted as a child. I also promised myself I’d put him through driving school and buy him his first car and now I’m so scared I won’t ever be able to do that if I have another child. His father has always said he doesn’t want another child but I told him and he made a comment last night about having a daughter. Like I don’t even know if I want to keep it. I’m so confused.