Up all night 'practising'!!

Annie
Oh my word, I'm so tired! I'm 36 weeks today with my third, my first was born naturally at 41weeks no sign of labour until the day apart from BH, second baby was born by emergency cesarean. This time I'm planning a VBAC. Well anyway, last night I started with very real painful contractions at 11pm they was every 6mins accompanied by backache and I couldn't walk with my knees together! The pains were strong, low down and included tightenenings but not usual BH feeling. By 1am the pain part subsided slightly and they was happening too often to be real, every 2-3 mins so I went to bed. Here I am now with no labour pains, but I have back ache and a very tender belly, almost like I've spend all night doing sit ups! Has anyone else had this ? Ps I lost part of my mucus plug 1 week ago but nothing more since