Regular painless contractions

I was wondering if anyone else has experienced this. so since I was 28 weeks I've been admitted to hospital twice with regular tightenings. I'm now 33 weeks and getting them again 4 mins apart, completely painless lasting 30sec-1min. I really don't want to go in again because they never seem to do anything and the contractions dont hurt. has this happened to anyone else? If so did you go full term?