Ay oo, totally normal yan mama! Carrying a 2-year-old all day is no joke, lahat ng mums I know complain about lower back pain, lalo na pag lumalaki na ang babies at mas mabigat na sila. Try to switch sides when you're holding baby, and do stretches when you can, pero kung talaga namang severe na or hindi natatapos, mas better na check with your doctor para sure lang.