I can relate. I didn't get a period from December to February. Now I have had it, off and on (but more on) since February 10th. SO annoying. Today, it has kicked up again, at a moderate level - clots, etc.
Pretty much the same thing happened to me 2 years ago, and I had a whole bunch of tests, which were all negative. Shortly after that, I was like clockwork every month, 28 days. Now this again. Along with it, I have the nausea. YUCK.
Of course, we recently bought a second home in Florida, and this had to happen 2 days after I got here!!!!