Thank you all very much.

You are absolutely right. I should have called the insurance or at least ask the doctor about the price. I assumed that the price would under $5000, which is the maximum of my student insurance. I'm still wondering the possibility here in the u.s. about negotiating on the price. I called all day yesterday and made some progress. my doc will provide a written notice stating that my symptoms occurred after the effective date. and the insurance company will re-consider my claim. I learned quite a lesson. Hope any who's on student insurance to be very careful with the policy. Thanks again for you guys kindly help.