Stressing out about being a good mom. Help!!

I'm 33 weeks with my first and I'm only 16. It was unexpected and has been one hell of a rollercoaster. Me and the father are still together, and he has been so supportive. I just get random bursts of being really emotional and stressed. I'm so scared and wondering if I'm going to be a good mother. One part of me just feels like I'll get so tired of it and so worked up that Ill just quit altogether and neglect my baby, which I would never want to do. I'm super nervous about this, especially as his due date comes closer and closer. Everyone around me has been having dreams of his arrival all of a sudden in the last week and the feeling that he will come early has just been eating at me since the beginning of the second trimester. I feel ready physically, and feel that we will have everything pretty much for the first few months since we have a stock pile that has filled my closet. But I feel so nervous about being emotionally and mentally ready. Most of the time I'm okay but I hate these random bursts of emotions.