Nervous

I’m a 20 year old student with 2 jobs. After 2 miscarriages in the last year, I am pregnant at 6 weeks with my first baby. I’m scared, but excited. My boyfriend of 2 years decided this isn’t the life he wanted and bailed so I will be a single mother. I haven’t often thought about giving this baby it’s “best chance” since I am aware I’m struggling however I know it might be selfish but I cannot get an abortion or chose adoption. I wanted to be a mother for as long as I could remember. I would appreciate any help.