Sleepless nights

Im currently at 20 weeks right now and i've been having sleepless nights these days. Will always sleep at 3-4AM and wake up in the afternoon. Is this normal? Also, i've been having these whitehead-like textures coming out of my nipples. Googled about it and it says that my breasts are getting ready for milk. But i've asked a few friends but none of them had the same issue. Is this normal too?