During April my period was a week an 1/2 late, and only lasts 2 days. I thought I was having pregnancy symptoms, I had lower back pain, always nauseous, sore breasts and sometimes dizzy. Then during may I think I had my period but it was a week late and I was spotting then got heavier and lasted 4 days. And my period is always on time. And I'm even more nauseous to more things, my breasts still are sore but now I get a tingly feeling in my nipples, my knees and hip sometimes hurt and I'm getting more constipated more often now and I still have lower back pain and very bloated. I took a test this morning and it was negative. What do you think is going on??