late period, tubal, cramps

Lauren
I'm now 6 days late for my period. I had a tubal 18 months ago, and I did take two negative tests, so I'm confident that I'm not pregnant. However, I am having tons of crazy symptoms and have no idea what to make of them. 
- was super tired for no reason about two weeks ago, for around three days
- kept getting randomly nauseous 1-2 weeks ago
- I've been slightly crampy all week
- intermittent soreness in my left side
- intermittent burning sensation on the left side of my old c section scar
- today I am so horribly crampy, my lower back hurts bad too. I'd almost compare it to labor. 
- random hot flash today
- random heavy breathing today, like it felt really humid only it definitely isn't. 
Any ideas?