Advise on restarting

Hi everyone. My son was born 11/11 and I was breast feeding for approx the first 2 weeks. It was so bad that small pieces of my nipple were coming off with the bleeding and scabing and I wasn't producing enough for my son so we're started supplementing with formula and I started using the shield. Mentally I was going through a rough time so we stopped all together. My question is, I still leak and I'm wanting to try breastfeeding again. Is it possible to build my milk back up or am I past the point where I can try again? I started pumping today for 15 min and plan on doing it every 2-3 hours which is how often he's feeding. About half an ounce came out. I've been depressed ever since we stopped and hopeful I can start back up. Thoughts?