Bottle feeding breastmilk

I have been having a hard time with breastfeeding so I have been pumping and bottle feeding her breast milk. I decided that I will bottle feed until she's 3 months and start breastfeeding again when her mouth is a little bigger. Her mouth is so tiny right now it hurts too much when she breastfeeds. I'v read that babies can have nipple confusion, but I don't really believe that. If their really hungry their going to end up sucking anything. I just hope that my milk supply will last. I currently pump every 2-3 hours and get about 3oz. I also bought formula just in case I don't make enough milk and I have it ready just for emergencies. I also have nothing against moms who use formula because even if formulas don't have all the necessary nutrients they still have some that's good for the baby. Some moms also result in using formula because of anatomical issues or because they just don't have enough time to breastfeed or pump. The most important thing is that your baby gets whats best for her/him.