Am I getting into a bad habit discipline wise?

Hi, so my 3 year old son loves to be told stories and every night before bed I do 2 of them and it helps him go to sleep (before he had major issues... screaming, yelling, kicking the bed, not sleeping, etc.). Now it's become routine and part of the night we all enjoy. We get to spend some quality time with each other which is precious since we only have like 1.5 - 2 hours after getting back from work to eat, bath, some playing or whatever else we have going...Then he started dipping back into old habits, where after the stories he would not go to bed, whine, cry... no more hitting/kicking though which is good. So lately I have been telling him if he doesn't help us all go to sleep after stories then he'll only have 1 (or no) story the day after. That usually works.Just so everyone knows I realize sometimes it's just hard to fall asleep and some part of that is normal. I always tell him he doesn't have to sleep right away, but that he just can't keep everyone up with yelling and whining.My question is... Am I getting into a bad habit with this type of reward/withholding form of discipline? Sometimes during the day he seems stressed or concerned he wont get 2 stories any time we get slightly annoyed with him or tell him off. We also regularly catch him picking at his nails to the point where they are bleeding which seems to be a stress response... which may or may not have a connection with his worry about storytime?Anyone have any input? Am I worrying too much? via /r/Parenting http://ift.tt/2qOaOqh