I had the same thing happen with my first lo when he turned 3 mo. I was FREAKED OUT! But after my period started, my supply went back to normal. A few days before my period each mo (until he was maybe 9-10 mo.) my supply would drop a little and he would get a bit fussy when eating. Nothing serious. Good news is sometimes it takes a little longer with baby #2. Didn't come back fully with this baby until 6 mo! Now that you know, you don't have to worry so much when your supply dips a bit - you'll know why!