Yes, muscle aches after exercise are normal. That's because you lack exercise. Sudden and strenuous exercise stimulates the acid in the body, making the body ache, and you can't lie down and rest when you feel sore. You should continue to exercise, so that you can get rid of some soreness, make your body strong and lose weight. You should control your diet. You said you should spend a lot of time in physical education class at your age. I suggest you walk home from school every day and stand up after dinner. Finally, my sister wishes you success in losing weight. Come on, students.