breastfeeding Help

I had my son a little over 3 weeks ago. the week after delivery, I did nothing but throw up or not eat. When he was 2 weeks old I went to the DR for emergency Surgery for a busted ulcer. While still at the hospital in recovery I end up with blood clots in my lungs. The past nine days at the hospital i haven't really eaten, on mass amounts of medications, and haven't seen, held, spoke to or anything of my son besides the picture on my phone. I've been trying to pump as close to my nursing schedule as possible. I started with getting about 18-20oz each session. now in a 20/30 minute session I'm getting a total of 2-4oz. starting to get discouraged and slightly depressed any advice out there would be much appreciated!