Soy intolerant but possibly not milk intolerant?

suzienickles36

My LO is now a little over 3 months old. We have been down the weird path of trying to figure out if he definitely has an intolerance or an allergy or just needs more time for his system to develop almost since he was 3 weeks old. I am exhausted and stressed trying to figure out what is best for him. We were on Similac Sensitive after BF didn't work out, and then he started having mucousy stools, I noticed a little blood 2 times, pretty much cried all day everyday for weeks, didn't sleep well at all, had very painful gas. Pedi suggested switching to either Soy or Alimentum. He absolutely refused the Alimentum. I tried powder, ready to feed, sneaking it in bottles with his old formula, etc. He literally stopped eating and was becoming dehydrated. So, we went back to the sensitive and he seemed like he was starting to do better. Not as fussy, actually happy and interactive, poops were better, and gas was still painful at times, but not all day, everyday. At his 3 month check up pedi still insisted we switch to soy to see if that helped at all. We started that Friday night, and he has been miserable. Screaming in pain, I notice his face turns a bright red color on his cheeks during some feedings, and very watery stools most like diarrhea. His gas has gotten worse too. I put him back on the sensitive last night as his intake was dropping as well. 

Long story short is it possible to have a worse reaction to soy than to milk based formula? I don't want to keep messing up his system and want him to feel better, but I am tired of the what ifs, and let's try this, etc. without a clear diagnosis. Even though from what I have read at this age it's hard to diagnose. Any help or advice would be appreciated!!