Breast Feeding Mommas

I been ebf my son since he was born...I drink like 2 cups of coffee in the morning and sometimes I need an energy drink later on... Especially if he doesn't sleep all night... He is such a good baby ...hitting all his milestones... At home he loves to play but when I bring him to my moms he hollars..like he's trying to talk but louder...my mom keeps saying its my caffeine intake ...that she has NEVER seen a baby be that loud... (I'm naturally loud when I talk) but he doesn't do it at my house or anywhere else... Now ...she called me this morning saying her medical friend told her it can effect his brain development... I don't mind cutting back but I feel like a zombie without it...has anyone else experienced this? He's my first so idk if it's normally for them to get loud like he does...

Please no rude comments...just asking if you have experienced something like this?