Am I a ‘bad’ mother?

I can’t help but it gets to me at times that my milk supply is decreasing & i’m giving formula milk to my 1 month old baby. I think mainly it’s because of stress. Am I able to bond with my child without breastfeeding her? Am I a ‘bad’ mom for not being able to give my breastmilk to her? Are there any ways or tips for me to make myself feel better or to get through this? It’s been in my head & it’s saddening….