The symptoms of milk stagnation can be seen in the following aspects: 1) early milk stagnation is mild and can be felt without any obvious sensation, while severe stagnation appears with obvious fever or pain; 2) young children show signs of refusal to suck, showing a sudden refusal to suck on one breast, which can be caused by the inability of the milk ducts on that side and the accumulation of milk, making it difficult for the infant to suck; 3) hard lumps appear in the breast, which generally soften after the infant sucks, but individual positions are still hard and different from other parts; 4) some patients show only local pain, but no fever or other discomfort.