Pregnancy brain

Hi all, 
I'm about 6 weeks pregnant and never really believed in "pregnancy brain" ... I don't even think it's supposed to happen this early on... 
But I am super forgetful lately.. I was taking out the garbage and had to do something else before I took it out and ended up leaving my house for work and leaving the whole bag of garbage on my kitchen floor. And today I was making coffee for my husband and took the ready made coffee to him thinking I was going to put the milk away after.. And ended up forgetting about the milk and leaving it out until my husband realized I never put it away.. Either I'm really tired or this pregnancy brain is real ..