You are not a failure! I have had a tiny baby as well! As long as she is eating and gaining weight give yourself a break! But yes, I always offer a bottle before solids. We also give her little snacks often!
As my pediatrician said, some babies are just small. Because we were always stuck in teen numbers but she did go to the 20s when we started food. There’s small adults, so there’s small babies No need to feel like a failure. If you did want to see if increasing the milk can help because 15oz seems a little less than normal
Some babies are in the low percentile and as long as they are continuing along their trajectory usually the doctors aren’t concerned. You can always add a lot of high nutrition/fat foods to their diet if you feel they might need more. Peanut butter, full fat yogurt/cheese, personally I give my baby grass fed butter before bed and he loves it.
I’m I. The same boat with my baby
My baby was in the 1% for the first 5 months of his life. After a week in children’s hospital due to serve acid reflux they told us the best thing you can do is offer milk before any solids because that’s where the nutrients come from. you’re a failure, you’re doing amazing!! A fed baby is a happy baby 🥳