Freakishly confused! Help!

So, my husband and I are actively TTC and my last period was Nov. 29th - Dec 4th. Now, I have been on BC pills for awhile now and this is the first month that I've been off them. I'm on day 34 of my cycle and I have yet to see a period in sight. No spotting - nothing.

But, I've had cramping (ranging from sharp twinges (I think this is scar tissue from a surgery a few years ago), to a consistent dull ache in the dead center of my uterus, to feeling twinges pulling at my belly button), lower back pain, dizzy spells, constipation, and a serious case of fatigue.

I took 2 early response pregnancy tests and they both came back negative.

Is it possible that I'm pregnant or is my body just freaking out from lack of BC?