Well I guess I must already have nodules forming after 16 days of estrogen. Cause just last night my nipples felt really sensitive and they also kinda itch now too, so I relieved the itch by massaging them and all I can say is "I'd buy that for a dollar" 

Hehehehehe

Im guessing the itching and sensitivity is going to get more intense soon. 

Probably.

Mine rarely itch, but I do itch them a lot...