Hi Faye
This might not apply to you, but I also thought I wasn't producing enough milk for Olivia - she'd often suckle then come off and be disgruntled as if there wasn't anything in my boob, in a paranoid state I'd then squeeze my boob and not be able to get any milk out so I convinced myself my boob had run out... then on Friday I went to a hospital specialising in sick children, I saw a nurse who is dedicated to breastfeeding and teaches the poor wee ones who have to be tube fed initially to learn to BF etc. I explained to her the above and she said it was most likely that Olivia wasn't hungry and so she was suckling and getting milk then getting annoyed or else she was being impatient at having to work harder to get the hind milk. She said that your boobs can't run dry as your body will just keep producing it, it will just take a wee while for it to get to the milk ducts and out of your nipple. She also said that the baby is much more efficient at getting milk out of your boob than expressing so me squeezing it and not getting anything wouldn't indicated I had run dry!
One night when I thought I wasn't producing enough milk I gave Olivia some formula (this was before I started expressing) and she guzzled it down to then throw up the whole amount - so I don't think she was hungry at all.
I don't think my ramblings have helped at all, seemed like a good idea at the time to reply but not sure it's relevant!
Like Urchin, I find drinking lots of water seems to help me feel more full and the nurse at the hospital told me to make sure my diet is rich in protein, especially in the afternoon to make good milk for the evening so I've made a wee tub up of nuts and rasins and put that where I BF for me to snack on.
HTH
Lucy x