What Causes Nausea, Cramps And Dull Lower Back Pain After Intercourse?

I had sex with my Boyfriend a week ago. I had my tubes tied over 8 years ago so we didn't use protection. Sense then I have felt nauseous, I cramped once & sense I was due for my period I thought I was starting. All I did was spot for at least 20 minutes, then nothing. I also had dull lower back pain one day. I sometimes feel headachy & moody. I cry all the time & I'm tired. Smells are also making me sick.