I worked to hard to balance my ph levels. and now i have to take antibiotics (amoxicillin) after a tooth removal. i heard that messes up your gut flora & overall vaginal health: what can i do to prevent it and keep my ph normal & how it is?

There is no need for healthy persons to attempt to "balance" pH, either in blood, urine, or the vagina. pH can be abnormal in certain vaginal conditions, but it is not the main thing that contributes to those conditions. Antibiotics do not affect pH anywhere in the body. Antibiotics indeed can alter vaginal bacteria, predisposing to bacterial vaginosis. But a few days treatment usually does not.