I'm sorry to hear you plan on leaving so soon, but I totally understand why, given your unfortunate set of circumstances, & I respect your decision in doing so. I will definitely miss conversing with you though! Hopefully I will follow suit soon (I just need to get my hands on the stuff first).
One bottle is certainly enough to quickly render you comatose but it might not be enough to kill you fast enough - It may just put you at risk of being in a prolonged vegetative state if someone finds you and intervenes too soon. You mentioned you currently live with your father, correct? If so, then I recommend going to a private and unknown location (like a nearby forest) to do it if you truly cannot bear to wait until your second bottle arrives. It will decrease the odds of anyone stumbling upon your body before you've fully passed on.