Irregular periods and spotting. Times.

I had my last period from 4-8/02/2017 and again got my period on 19/02/2017 (took one ipill last week), frequent white vaginal discharge and major hair fall, acne, breakout in t zone of the face, also I smoke every day. I feel tired most of the tired given I sleep sufficiently and also suffer light headedness. My iron count was 14 the last month when I got it checked, please tell me mainly about how to treat irregular periods and vaginal discharge. I'm always worried about spotting or getting my period any moment, I smoke 3-4 cigarettes everyday (menthol ones) and drink very less water, almost a litre. I mostly starve myself as I avoid eating junk at college which is all day, which is troubling for my health as my metabolism is really high and I eat very very less. I have been active in sexual course for the last 2 years and have taken after morning pill a few times.