Thanks guys, you've made me feel better.
I'm trying to extend his feeds a little, and yes, not to obsessively weigh him! Seeing the paed next week just in case, for my peace of mind.
LMS, yes, I'm just feeding through the fussy stretches and hoping it helps. He latches on fine, eats for a few minutes and then fusses. Having said that, he's been waking more at night for the last ten days to make up for it. I just feed him through it, thinking I'd rather feed than not, just in case he's hungry. And he always seems to be hungry.
Last night was the first night in a few where we seemed to be back to our "normal" routine, which is one night waking at about 2-4am, for a quick feed.
Encouraging to hear about your daughter!