This is the second time this has happened. Both occassions were in the evening, the last feeding of the night for my three month old baby girl who sleeps through the night. This happened last week and tonight. I was nursing her and she was doing good but during nursing it appeared that I did not have enough milk for her. She got very frustrated and acted like there wasn't any milk coming out. I attempted to express some myself and very little came out. She was very upset and crying and I was not able to get her to stop crying so I knew that she was still hungry. Luckily I had some breast milk in the refrigerator that I had expressed during the middle of the night. She was eating fine during the entire day but for some reason tonight and another night last week I have run into this problem. What could the reason be?? Or what could be happening? It concerns me and I am worried. What should I do? Also, what would I have done if I didn't have any breast milk for her in the refrigerator?