Is the 20% very different from what you were getting on practice tests? If you were getting much higher scores it may be that you bubbled things incorrectly and then there is a case to be made to take it again. But if not, I would not bother to spend money on the application fees to Andover and Exeter. If there are other less competitive schools you are interested in, I may give it a shot. Also, I don’t see upthread whether you are FP or seeking FA, the latter would make things even more of an uphill battle. If you were my child I’d say scrap the BS project for now and shift focus to being engaged and doing well in your current school. But if the applications are already done and the fees are NBD it may be worth to submit just for the ‘you never know’ theory. That is if you can submit, forget about it and move on with life. If it will suck all your emotional energy for another 2-3 months it is likely not worth it.