abnormally long, but light period?

My last period started about 3 days early, and was very light throughout the entire thing. I have been on the pill (tri-cyclen lo) for three years now, and never once has my period started before the first day of my sugar pills, and it has always been the same flow (regular).

There was one day a week or two before my period started that I took an iron suppliment pill, as well as a women's multi vitamin that containes a decent percentage of iron. I have also started taking Ritalin for my recently diagnosed ADHD, and took all of those pills at once in a rush that morning before work, and didn't get a chance to eat breakfast with it. When I got to work I immediatley went to the washroom and threw up, and had a terrible migrane (migraine) for the rest of the day.

Could this have possibly contributed to the abnormal period...since iron levels usually largely effect blood issues?