Hun Matilda was a difficult baby from 10 days old... she screamed 6-8 hours daily until... well... she was 3 yrs old. Now she still has screamy days but not as much. I've spent years going to health nurses, paediatricians, Triple P courses, Social workers, allergists, behavioural paediatricians, Occupational Therapists, Child psychologists....

A few things really set Matilda off. The biggest thing we've found is she has 2 things diagnosed so far, one is a severe allergy to cows milk, the other is she has "Sensory Integration Disorder" and we are in the diagnosis process for Asperger's Disorder.

As your bub is only little, I would suggest trying something like a food elimination diet, cows milk is nearly impossible to avoid in a FF baby unless you get a script from your GP for an elimental formula to rule it out. You can use goats milk formula, its probably the closest thing to breast milk anyway.
Often times if you catch the food issues early on, you can avoid further issues.

Jovie is allergic to cows milk as well, but doesn't have the issues Matilda has.

Something like a food elimination diet may sound sort of airy fairy... but maybe check out the "fail safe diet" it rules out foods that are known to cause behavioural issues. One Asperger's woman I know says that when she has any dairy, her IQ drops 30 points... she can't focus and has meltdowns. Its worth seeing if its food now before she has access to any others

Goodluck