Crampless period??

I'm due to start my period around Thursday depending on what my body chooses. 
I'm on birth control and during the placebo pills I usually start bleeding that first day or on day 3. Never before, never after. 
About two weeks ago my breasts got really sore, typical for me except this time was pretty bad. Then sometime last week I managed to avoid sleep due to miserable lower back pain, something I NEVER experience. It only lasted about two days.
I'm now seeing very visible veins down my breasts through my abdomen, down to my legs. NEVER seen these before or even honestly considered they were even there.
It is now Monday and by Wednesday of last week I should have started feeling minor, dull cramping in my uterus, pre-period cramping. Nothing. A little bit of white mucus but no cramping.
Not an ache not nothing. Even with bcp. I'm hoping I'll be skipping a period altogether, but as this is only month 5 and I always, ALWAYS know when my period is coming and she ALWAYS comes, this is an odd change for me. 
I've also been feeling very sluggish the last few days and am considering possible pregancy so I will be testing if lady red doesn't show, however, I'm curious if anyone has ever experienced "crampless" light periods before?