Someone in my building is smoking crack and I'm smelling it all the time. What affect will it have on me? If you don't smoke crack and you think someone is what should be done?

Yes it is possible, if you are aware of it, report it.

Second hand crack smoke can affect you if you are in the immediate area its being smoked, but if you keep smelling it, report it to the cops, or landlord, or building manager.