Come on, food allergies are overblown, and do not cause incontinence or bedwetting. And frankly, you should not undergo tons of tests for bedwetting because the vast majority (99%) outgrow it by 10 years. There are risks to testing, and frankly it is not worth it most of the time as a cause is never found. For your case, I'd consider vasopressin which may help you to concentrate your urine at night, and so decrease bedwetting.