50% Effaced and Cervix Dimpled

My midwife sent me to the hosp last night because starting yesterday I was having to many Braxton Hicks Contractions. At the hosp I was told that I was 50% effaced, My cervix was dimpled (or not shut all the way), baby was head down and dropped. Has anyone else gone through this? I'm worried about about having her way to soon. Should I be 50% effaced at 28 weeks?