Hey S.!
I'm a doula here in Austin with getbabied.com, and I'm a mom of 2 with one in the oven, and I can definitely say each pregnancy is different. And, yes, your second can feel really low for a long time, even at your 2nd trimester. My second was so low at his 18week ultrasound, the techs had a hard time finding his head. (It was that low into my pelvis.) With second or third time moms, they also don't necessarily feel their baby drop right before giving birth, b/c either the baby has already been engaged for some time, or it does it during labor. It's also normal to start feeling contractions earlier. Sometimes what feels like a contraction, though, could totally be your bowels moving. :).
A. N.
austin, tx
http://getbabied.com