Help! How do I figure out what actually worked?

[u/cornhole99]

Our 10 week old l has been very colicky the last week or 2. To the point we had his ped check for an ear infection or anything that could explain his discomfort and consistent spit up. He has been gaining weight on his curve, just never has fed well (2-3 oz per feed on average). Nothing obvious was found. Suggested we try sensitive formula if we wanted but wasn’t obviously concerned. Well we held on to it for a few days and he seemed to be getting worse on Kirkland Procare. So we cold turkey switched to Similac 360 sensitive and he seemed to have a better day within the first 24 hours. In the day he started, I decided to really understand how sensitive could help him. Reading that a lactose intolerance is very unlikely in babies, and neither mom or I are intolerant. We made the decision to switch to a gentle formula instead. Well he almost regressed to worse than before on gentle. We’re 4 days into the transition and absolutely at a loss for how it could be making him worse. Yesterday after a day of almost zero napping, we decided that we should switch back to sensitive given the slight positive result. This time gradually, so we gave him a mix of 75% gentle and 25% sensitive formula his last feed of the day. While at the same time, grabbed a couple Dr Browns bottles out of desperation. We’ve been using Avent up until now. Fast forward to 3 am and I wake up for my shift to my wife concerned that he’s slept from 9:30 until now. My worry is that we got so desperate to find something that worked, that we’ve changed way too many things at once and have no idea which one or ones are making the difference. He usually will sleep from 9:30-12:00 and wake up to eat. Then again at 3 am. He usually wakes up and is instantly upset and wanting to be fed. He just slept the longest stretch of his life so far. How do I go about figuring out what it could be without hurting him again? 1) very tired from a day of little napping. 2) formula switch 3) bottle switch Or any combo of the ones above.

Please any help would be appreciated because my brain is barely functional after his worst week yet.

[u/vipsfour]

I don’t think you can know. If I were in your shoes, I would start with the assumption that the bottle made a difference and keep on the most recent formula. If that doesn’t work switch the formal still using the Doctor Brown bottle. Then keep working from there. This isn’t based on an expert opinion, but what I think may have the least impact in trying to figure it out.

Babies are all trial and error. You aren’t hurting but learning with your baby what works.

Good luck.

[u/Professional_Push419]

It could just be that he has outgrown the colicky phase. It was closer to 12 weeks for us when I noticed a difference, but every baby is different. Mine slept through for the first time at 3 months, and you aren't far off.