Oh thank you so much for all the replies ladies! Just been tied up at work and amazed by the responses. Plenty to try there to try to prevent them and good ideas for how to beat the buggers next time they start 
Sympathies to loveinacoldgrave, littlestressy, myrealname and others also suffering but I was very pleased to read not to worry too much about how I'm going to cope with contractions from this response. I was hoping for something a little more, errrr, serene on the big day and I wasn't very ladylike at 5am this morning when stricken 
Buying more bananas - I agree they helped me before slainte and i love coconut water so thank you handmini for giving me an excuse to justify those expensive cartons of the stuff that my OH raises his eyebrows at cause they're £2 and everyone drinks them in my yoga centre so he thinks they're all a bit 'designer drink' so I just usually take my own OJ for cheapness sake. Looking forward to grinning sweetly and saying 'but it's to prevent my cramps, dear OH'
Thank you for the tonic/quinine tips I'mnotaslimjim, rosec, jeanlouisefinch, ladyword,, balloonslayer and voodoomunkee I love tonic - usually with gin and lemon so will try this evening and pretend it's got gin in it.
woodifer, fourbears, silversmith,kazyr and ybr - thanks for the stretching tips. I'll def try this. If I'm with my OH he always tries to stretch me but they're so bad he'd be liable to get a kick if he tried so will try for myself.
beebopbunny not sure about the pillow making a difference but my pillows are a bit flat but will try again with a better one. I have a nice big yoga boulster I can lie my top leg on to try as I keep losing the pillows like silversmith
Off to get some supplements idlevice and brianmayshair as I'm allergic to milk so maybe short on calcium and perhaps not enough in my multivit.
Pears soap is worth a go stabbing and failing that, going to roll around on the kitchen floor wigglesrock
Yeah! I feel really positive I can try some stuff even if it's just something you have to live with for a bit but horrible feeling helpless.
Thanks again 