how to "up" my supply?

FORTCSZ2012

im a ftm and i ebf. i believe that between both of my breasts, my 4 week old is getting enough during the feedings (though, she fusses and pulls off and then eagerly latches back on, barracuda style multiple times during the feeds)- but how do i "up" my supply? it seems like a lot of women on here breast feed with one breast at a time- and i seem to need to alternate. aside from this, my husband is adamant that i have some breast milk on reserve in the fridge/freezer so we can have date nights and such- but i only seem to produce just enough for feedings- no extra to have "on hand"- when i first started breast feeding and pumping, it seemed as though i had more than enough to go around. does anybody have any advice on this? im feeling super guilty that im not producing enough or something wrong.