TMI - Nipples 4w1d

This morning I woke up with my nipples stinging sort of. They only hurt when they're touched. I thought I noticed it yesterday when I had a shower but it was only once. This morning I woke up to them hurting and then when I touched them they stung. They've also been "standing at attention" and the tips have turned white. Is this what people are talking about when they're boobs ache? This didn't happen for me until my boobs started to grow with my son 6 years ago.