Desperately trying to breastfeed

I've been having a mare with it. My baby was born via C-section 13 days ago and I've been desperately trying to breastfeed. I had midwives and other homestart folk coming out talking about latch and supply and all that jazz. It was going ok at times but my baby seems like she's not getting enough. She started feeding for shorter periods of time and about 5 mins into feed she's pulling at the breast and seems upset that nothing is happening. I've tried everything. Putting back on the same breast, offering both sides, pumping an hour after feed to build supply, breast compression whilst feeding etc etc ... I always have to substitute with a bottle that she necks like she's not just literally finished feeding. If I skip the bottle she's feeding every hour. It's soul crushing. Any advice?