I'm not sure what you mean by "whistling". Do you have more than one #3 reed, and do they all produce the same "whistling" sound? It could be just that particular reed.
As far as the sore upper lip goes. Are the sores where the lip contacts the metal of the mouthpiece? I would start by washing the mouthpiece thoroughly with hot soapy water and a brush. If the sores continue, your skin may be having an allergic reaction to the plating on the metal mouthpiece. I know some brass players who have had their mouthpiece gold plated because of problems with the silver. It may be that you can only use plastic and hard rubber mouthpieces in the future, and that is not necessarily a bad thing.
As far as the sore upper lip goes. Are the sores where the lip contacts the metal of the mouthpiece? I would start by washing the mouthpiece thoroughly with hot soapy water and a brush. If the sores continue, your skin may be having an allergic reaction to the plating on the metal mouthpiece. I know some brass players who have had their mouthpiece gold plated because of problems with the silver. It may be that you can only use plastic and hard rubber mouthpieces in the future, and that is not necessarily a bad thing.