Have you been officially diagnosed with anything yet and have you had this problem with fearing illness before? Would shaving your beard make it easier to see all of that skin area....opposed to looking in between the hair? Maybe rethinking with positive thoughts would help - like....if I have this, there's good treatment in the early stages etc. If you don't have a therapist you should be evaluated to determine what's the origin of this fear - for example it could be obsessive thinking or hypochondria and others - not saying this is what you have.