Sneezing, a watery nose and red itchy eyes that flare with dust or fragrances point to allergic rhinitis rather than an infection. The ongoing cough on top of this is likely from the same irritation, plus even one cigarette a day adds extra irritation to your airway.
Next Steps
An antihistamine can help the sneezing and eye symptoms, but get it confirmed and chosen by a physician rather than picking one yourself. Cutting out the cigarette would also ease the cough considerably.
Health Tips
See a doctor sooner if breathing feels tight, the cough brings up colored mucus, or symptoms spread to your chest.