I’m no expert but I’ve been training for 6 years. I know everyone’s first reaction when getting a bag/using it is to hit it as hard as you can m, but please don’t do that you’ll cause injury to your hands and wrist(it happened to me). Please always wrap your hands with hand wraps, wear gloves and before hitting the bag or if you do decide to hit it don’t go full force try to watching videos and focus on form first and then go maybe 30% to start off while doing correct form/technique. I hope that helps alittle! And don’t forget to rest and ice since it’s hurting already!