Child Support payments do get reported to the credit agencies and do show up on your credit report as to whether the payments are being made on time or if the child support payments are late or are not paid.
If you make your child support payments on time you shouldn't noticed a drop or bad impact on your credit reports but if you miss payments on child support or never make the child support payments then the court will report the late or missed payments to the credit agencies which can lower your credit score substantially.
My brother owed child support and decided to never pay the child support payments again and his credit score dropped from 700 down to 500 plus he went to jail for awhile for not paying the child support.
Never decide to not pay child support payments because it can hurt your credit score and get you into trouble.
If the child is truly yours then you need to support them.