I am 43 and a smoker, my doc prescribed a low dose oral contraceptive w low dose estrogen; should i avoid this?

Yes: Estrogen containing contraceptives are contraindicated in smokers 35 and over because studies show that the risk of blood clots, strokes, and heart attacks is unacceptably high in women of this age who use both estrogen and nicotine. I would strongly suggest that you either consider an alternative estrogen-free method of contraception or that you immediately quit smoking.