Exclusively Pumping Help

I’m a FTM and have a 5 week old. My baby girl was born weighing 8 pounds 4 ounces and we dropped to 7 pounds 3 ounces. Saw a lactation consultant twice due to poor latch. It was emotional for me as it would take 30-40 min for baby girl to get a good latch to and it hurting really bad so I’m now exclusively pumping. I’m pumping every three hours and feeding baby girl every three hours. When I was breastfeeding I was pumping for 10 min afterwards and was able to get some milk stocked in the freezer. We have been giving baby 3 ounces. I’m only able to pump anywhere from 2 1/2 to 3 ounces each session so sometimes we have to add the frozen to what I pumped. Baby girl now weighs 8 pounds 9 ounces. Is it ok to not wake her up at night to eat and for how long can she go without eating? I’d like to let her sleep longer at night but scared of what it will do to our pumping and feeding schedules. I don’t have enough stocked to give and then pump. I’m a stay at home mom and pumping with her is sometimes a nightmare. Sometimes I just have to let her scream/cry until my pumping session is over. Any advice is welcomed!! I have a feeling supplementing with formula is around the corner. Which is fine with me; not so much with my husband. HELP!!