Am I in early labour... 38 wks ... baby #2 ?

All last night from 7:30 PM I've been having contractions that average around 12- 11 min apart. Pretty painfull period type cramping . They make my back tighten and wrap around to my lower belly... walking does not make them go away ... Also drank lots of water but they r still coming. Its now 11:27 AM... Last Tuesday midwife said I'm 3cm 80%effaced and babies head is engaged and very very low ... I've had tmi sorry loose bm all day yesterday and today...I haventhad a bloody show yet ... Does it sound like I'm in prodomal labour? Thanx ladies. I know I sound silly bcuz this is my second pregnancy but my first didn't start out like this... I just woke up n noticed my waters broke and contractions were deffinitally distiguishable.... Any thoughts and opinions plz thanx