First timer!

I'm 24 and literally just took the pregnancy test last night and another this morning. I was late by three days which is what prompted the testing. I have no doubt in my mind I will be a good mom because I come from a huge loving family. I do have a couple dilemmas 1.) I am a smoker and I don't know the best way to quit 2.) I am a very negative thinker and I'm already stressing about the pregnancy going wrong. Any advice on breaking bad habits and keeping a positive mind and outlook for the pregnancy?