Tool, I'm guessing you're referring to your nasal mucus, not throat or chest, right?

If you're terribly worried about it, go to the doc. But most likely what's happening is that your nasal passages are simply a little dried out and irritated by the smoking and the irritants in the smoke, and that can make you more prone to little broken capillaries or small broken blood vessels. You could use one of those plain saline mist nasal sprays to add some extra moisture in there. Or just breathe some steam that's coming up from a pan or kettle of boiling water. Try not to worry too much about it, OK?