I have a cream ale on my secondary for 2 weeks now and a week ago I checked the gravity getting access to the beer with a thief. I sanitized the thief with star san but I just sprayed it really quick and rinsed with water. I know i dont have to rinse I always do. A week later I noticed a 2 white rings around my better bottle. Not on top of the beer just around the rings of the bottle and at the bottom. Could this be an infection or is it normal?