Questions About Effacement, Twin Pregnancy

hey everyone! i'm 34 weeks going on 35 weeks pregnant with identical twin girls. this is my 1st pregnancy. i should have asked my OB these questions but i always forget them&by the time i get home i have a million thoughts&questions going through my head. my cervix is really short&im 60% effaced&2cm dilated. ive been having lower back pain, period like cramps, loosing alot of mucousy discharge, braxton hicks contractions&my babies have dropped. i was put on a medicine to slow down the process of labor because i was really dehydrated&had to be admitted to my hospital because of the regular contractions i was having. im still having alot of braxton hicks contractions even with being on this medicine. anyway, my question is, how much longer do i have til i go into legit labor? is anyone else going through this?