Yes you can, but I think you should at least tell us why you don't want to go brighton and sussex med school, if its because of prestige or you hate both locations, or the course structure, because its a massive risk to apply again, you may get a higher UKCAT, but you will have to do more work experience, volunteering, and have to prepare for interviews all over again, to do the same course but at a different uni, and come out with the same chance of getting a job as if you went to BSMS.