Hi Rusty,
I have had the same as this, i think its a combination of a hungry phase for baby and getting used to feeding and the sensation not being so strong.
I have fed Sophie normally but at night
b4 she settles she is demanding more, getting frustrated cos she has drunk me dry and then me feeling like i dont supply enough. (never expressed so no spare bottles either)
I have been drinking plenty, and trying to feed reguarlly through the day to build demand up, it worked in that yesterday she was full at breakfast and then didnt want much during the day, which left me at bedtime with a simmilar problem once she drank that!
Try the usual things but put it down to Harriet having a hungry phase and remember as we feed more the sensation does lessen, fairly soon it is normal to put baby to breast and not get too much of a sensation, remember the toe curling pain at the start, then its just the let down, then that should ease too.
Hope i help, like i say Sophie going through the same, i keep being tempted to supliment with a bottle but i know i can do it, i have 3 times b4!!
Take care
Pinky xx