It's okay. Just after exercise, aerobic glycolysis in muscle was insufficient, and anaerobic glycolysis replaced it, which increased the concentration of lactic acid in muscle tissue and produced accumulation. During the reporting period, the nerve endings in muscle were stimulated, resulting in pain. This shows that the effect of exercise is still quite good. Stick to it for not too long (two to three hours a day is better) to avoid muscle strain caused by excessive exercise.