I keep accidently biting my new lip pircing?

i just got it yesterday afternoon and i keep accidently biting it and it hurts sooo much and everytime i eat it feels like my fake ring( that i wore to see if i would like a lip ring or not) so i keep trying to push it out. but ofcourse i cant cuz its actual pirced now , so what can i do to stop biting it so much i am already eating more slowly and with lil bites and tring to chew on my other side? also will it fall out? or will it start to bleed alot? and my pircer said after 10days i could change to a shorter bar for my stud should i or should i wait longer i already have another stud my mom is giving me cuz she has her monroe pirced and she has studs she dont use anymore cuz she dnt really like diamond studs.