you are almost past the point where infections show up so that's probably unlikely. before you call your surgeon's office have someone look at the area. is there build up because rinsing routines might have changed to not rinse there as well (we use t-sal shampoo for scalp skin plaques that build up, happens with stress, but it would help remove other build ups). if it is red or at all puffy around the surgical scar or shunt bump, get in right away! if nothing is visible, keep an eye on it as you may be having a reaction to the implant materials or something from the surgery, that should be unlikely but rare stuff happens. I can't think of other stuff we look for but maybe someone else will have a suggestion.