I don't usually get sore after workouts. I give myself at least 48-60 hours of rest in between. Like yesterday I did 6 sets of pull ups til failure, barbell curled a weight I can only do about 12 times for 4 sets and I did T bar rows for 3 sets. Yet I dont feel any soreness in my biceps, does this mean my workouts are not building any muscle? Is it normal to not feel sore?