very low supply 😩

My baby boy just turned 4 months and I've been struggling terribly with exclusively breastfeeding. I've researched until my eyes are crossed, trying remedies with lactation, reading books, and even nurses tried to help. Power pumping has only left my nipples sore and swelled. I still nurse him and mostly he's still hungry and uses me a pacifier lol. On average first thing in the morning I pump .5 to 1oz then the rest of the day less than an ounce until I pump again the next morning. I'd really love to be able to get my supply up to store for my little guy to go to day care in a few months. Am I missing or not doing something right? Please reply with suggestions 💙