37.3 wks... could this be the onset of early labour? ?

To start I'm 37.3 weeks with baby #2... At my appointment last Tuesday my midwife said I'm 2cm 70% effaced and baby is very very low! For the past week I've had very loose bm ... I've been loosing my plug no blood in it though.... And lots of bouts of bh contractions ... The past 2 days I've had very painfull contractions but nothing I can time. Also some pain in my cervix ... They were about 27 min apart then 19 min apart then again this morning with period type cramps...along with lots of pressure and pelvic pain... I had my first child at 38.6 weeks and I also had period type cramps for two days before my waters broke... Does this sound like labour is coming soon ? Or wishful thinking? I have an appointment tommorrow ...oh and I've heard that second babies come sooner than first babies? Is this true? Thanx ladies