The only thing I've left till last and never have gone through till now is logs. My question is is it possible to completely understand it in one day?
Yes You could watch all of the exponentials and logs videos on examsolutions.net and do all of the practice questions in less than half that time. This would leave plenty of time for more past exam questions or text book practice if required. Whether you will "completely understand It" will depend on your aptitude for maths.