I think you are putting up your own barriers. You need not have your parents' consent to see a doctor. And when you do your health MUST be kept entirely confidential including from your parents. As for how to get there that shouldn't be a hurdle either. There are multiple other methods of transportation other than getting your parents to take you... Is public transit available? What about taxi service? Call up the crisis network; they may be able to arrange for your transportation. Call up the local mental health association; they can get you picked up.

Where you really need to go is a hospital or minor emergency clinic to get that immediately looked after.