My regular period flow start and lasted for 4 days and post that I had light spotting for 9-10 days. And after a gap of 3-4 days light spotting started again. Which lasted for 2-3 days. And now after a gap of a week today again the light flow/spotting has started. I'm experiencing this for the first time. Is this normal? I have taken medicine for cold montelukast and for headache saridon or naproxen. Can this be a side effect of any of these medicines?