No let down, please help

I'm 6 days post partum and my milk is finally coming in. I woke up to extremely painful engorged breasts and I have tried everything I can to try and pump the milk out, but I'm lucky if I get 5ml over multiple sessions.

I've always had trouble with the LO latching, even with a nipple shield he's had trouble latching on and he's never had much interest in the boob anyways. So I've decided to supplement with formula until my milk came in and start doing bottles.

However even now when I know my breasts are producing milk or preparing itself I can't get a letdown. I've tried everything I could find to help but nothing has worked. From hand expressing, to compresses, hot showers, massages, manually pumping, Etc. Nothing has worked for me.

I use a Medela Maxflow pump provided from my insurance and honestly it's pretty lackluster. My cousin gave me a Spectra, which I'm waiting for flanges to come in for so haven't used it, and I'm hoping this might be a bit better, but the flanges won't be here for another 3 days and I'm in absolute pain.

Please I need any help you can give, I was going to try and reach out to a consultant but there's a winter storm coming in the next few days so I won't be able to see them until the end of the week.