Breastfeeding baby with cow milk protein allergy

Today my little one had some bloody mucus in his stool a along with some very foul smelling poops and gas in the past couple of days. He is exclusively breast fed so the rancid smell of his poop was concerning to me, so examined each diaper closely and found mucus and blood. After taking him to the doctor they think he may have a cow milk protein allergy. I am removing dairy from my diet to see if that helps. I am lactose intolerant so I dont eat a lot of dairy to begin with, however I do eat a lot of soy products. I have a tree nut allergy so most of my non dairy alternatives are soy based. The paperwork I received from doctor said i should also cut soy from my diet, but i fear it will be close to impossible to eliminate both dairy and milk. Are there any other breastfeeding moms out there who have gone through this and have any recommendations or advice? Did you give up dairy and soy or just dairy? Anything is appreciated. TIA 😊