Please help - expressing

[BornAgainBokononist]

My ds is nearly 8mo, bf with no ff since one month old. However in the first month he had top ups, I didn't notice any reaction but he had awful awful colic and I'm wondering now if I'd have been able to tell? With the constant screaming, wind and stiffness.
The reason I'm worried now is that he has reacted very badly to weaning. I can't seem to express at all any more so mixed in formula to his food. I don't know whats causing this reaction so I want to express to mix in and try that.
I tried today with my hand pump, when he was young I expressed regually and it went well. In the end though he just fed off the breast. I tried for an hour today and didn't get one drop. When he feeds he's definately getting milk so why can't I get any?
I was calm, had a pic of him and well watered and fed, not one drop. Has anyone any experience of this or advice? I really need to try breast milk with food before doctors and pediatrition.

[pommedeterre]

I think that lots of women have trouble expressing but that it is not a reflection of your milk production when he feeds.
As an aside - is there a reason why you don't want to use full fat cows milk in his food? It can be used in food from 6 months but not given as a proper drink until 12 months.

[BornAgainBokononist]

I've never heard that before, thanks :)
There's concern that he's lactose intolerant which is why I wanted to test with bm first, don't know what to do if I can't express though. Can I use water as he's still feeding from me?