The Police won't come looking for you this weekend for a warrant just issued. It could actually take over a week before the warrant is live and on the system. If you hand yourself in, as advised earlier, don't go later than midnight-1am as technically they could keep you til 'next lawful day'. If you have meds with you make sure they are in the box with your details on it but you won't get meds for 1st 6 hours you are in custody.