Graduate entry medicine is hardcore, a lot more competitive then undergraduate medicine, you need to look at the other applicants, look at their degrees, where they placed in their batches, and consider if you can compete with them. Also make sure you know why you want to be a doctor, I believe a lot of medicine applicants are in it to help people and they would get the same level of satisfaction, if not more, by becoming a nurse. I think you'll find that you can ascend to higher levels than a lot of doctors as a nurse, have your own practice and lead other people through being a nurse consultant.
The benefits of being a doctor are that you have more responsibility, can apply to more postgraduate roles, take a wider approach to treatment as you have medical knowledge that goes beyond your specialty, plus I think people respect doctors more than nurses, which is unfair but that's just how it seems to work. If you think those are good enough reasons to spend 4 extra years in medical school when you could be earning, having a social life and being involved with treating patients as a nurse then go for it.