Is this normal? TMI!!!

I'm noticing crusty stuff in my bra where my nipples go and on my shirt when I don't wear one. I'm 14w5d with twins. I don't know how early you're supposed to lactate or leak. This is my first pregnancy. It's more out of my left nipple than my right. But my left boob is smaller than my right also. I was going to call my doctor and ask but I have an appointment next week and I've called almost every day the last week for other problems and I feel like I'm just annoying them with stupid questions and coming in over non sense.