Preterm labor questions

Britney • Isaiah William 9/9/15! ♡♡

I was told by my midwife that I should watch out for preterm labor now that I have hit 30 weeks. Due to being tiny, under weight before pregnancy (I was 92lbs pre pregnancy and now 117lbs).. also I just found out I have bacteria vaginosis and on antibiotics for that, I smoke (no judgement please.. I have went from a pack n a half a day to 2 smokes a day) and I'm not sure if it has anything to do with preterm labor but my son is measuring a little bigger then the usual. Hubby was almost 12lbs when he was born.

Anyway, due to pregnancy brain I forget everything she said.. but I think she said if I have 4 or more contractions in an hour to go in? Is it normal for you guys to get a contraction almost every time you stand up? The contractions don't hurt, which my midwife told me that it's fine that they don't hurt but to still think of them as contractions and not Braxton hicks. So I've been paying attention to them.

Maybe I'm just overly worrying? I also had a very VERY small gush of fluid today but it smelled just like normal discharge and not anything else.