Okay, so the first thing you want to look at is the
TSR graduate entry medicine guide. Because your first degree is not in a science/health/life sciences subject, you're not eligible for all of them, but you are eligible for about six of them (would be seven if you had an A Level in chemistry), which is good enough if you play your cards right.
Read through the guide first, and then visit the course pages on the respective universities' websites and read through what's required (Warwick reportedly
requires something like 70 hours of provable work experience), sort out some long-term work experience (and continue the hospital volunteer role if you're still doing it and if possible), start preparing for the relevant admissions tests and then, hopefully, you should be ready to make a competitive application in October.
Also, the Band 2 bit on the UKCAT only indicates what you got in the Situational Judgement section, which is typically less important than the total (out of 3600) of the four other sub-sections. What did you get on those?