Please help with tumbling fear=(?

okay so i got my roundoff backhandspring a couple weeks ago and at cheerleading practice i just kept throwing it and it was so easy and i get alot of height but all of a sudden i just cannot do it. im so scared to do it without a spotter and when my coach spots me i do it perfectly and she doesnt even touch me. im so scared because i keep picturing myself stopping mid air and falling on my head. i need to get it back before competition in 2 days! please helpppppp<3