Hi Pet,
Some moms take longer than others to let down to a pump. It sometimes took me 30 minutes. And then it's important to hand express afterwards to be sure to get every drop. Fenugreek and blessed thisle herbs and help you. We usually suggest 3 capsules of each, 3 times per day.
You can try breastfeeding with the help of a Lact-aid
www.lact-aid.com filled with formula until your own milk comes in.
My son did a breast refusal thing when he was about 8 months old. I found it helped to nurse him when he was sleepy.
And the best advice I can give you is to contact a board certifed lactation consultant to assist you. You can find one here
www.iblce.org Just click on the "About IBLCE" button at the top of the page and the US and International registries pop up.
Best,