Can this mean my baby is lactose?

Angie • Mommy of a baby boy with wings 👼💙 Soon to be mommy of a baby boy 👶💙🌈 💙Forever in our hearts Ethan Emmanuel Robledo Sanchez👼💙

So my little one has been spitting up since he has been born he has been formula feed this whole time. He will be 4 months on the 12th he eats at least 6oz I have tried to reduce it but he gets really cranky and also I burp him during his feedings but still ends up spitting up his pediatrician currently gave him medication but it doesn’t seem to be working it actually probably made it worse. They think he has GERD and the medication they gave him is called famotidine. He currently pooped and it seems as he has white little balls in it. I plan on maybe giving him soy formula since the gentlease didn’t help him either hopefully with the soy formula it helps him. But this is a picture of his poop what should I do all they keep telling me is feed him less which I have tried but he gets cranky they also tell me burp him during his feeding and I do that. That’s all they tell me. But what do you mommies think I should do? Please help I feel like he is uncomfortable at times I also gave him gripe water to see if it helps him but it doesn’t. I just want my little one to not spit up so much.

As you can see his poop gave him a rash. I put rash cream when I changed his diaper. This was from about 55 min ago

This one is from the morning it was 10:30am