Measuring ahead

So I'm technically 29+1 today . However I've always thought I was further along then ultra sounds say . Today I went in for the routine check up and I'm measuring in at 35 weeks 5 weeks and 5 days ahead of time . They are sending me in for an ultrasound within 2 weeks to get a measurement that way . Dr said usually the measurement taken from the tape is correct however she needs to confirm it via us . Either I'm ahead of time or there is lots of liquid in there has this happened to anyone else and if so what were the results . also I'm experiencing braxton hicks . anyone else go through this ? Please share your story .