Switching from biomedical science to economics?

This may be a complete long shot, but I figure it can't hurt to ask.

So I am about to enter the 4th year of a BSc in Biomedical sciences and I have just found myself completely disillusioned with the course (although if I am honest with myself, I never wanted to do the course in the firs place). I do intend to graduate but rather than follow the route of becoming a biomedical scientist, I have been strongly considering doing a graduate diploma in economics and pursuing some form of higher education in economics.
I have not heard of many people making such a switch, but I can not imagine that it is impossible. If anybody has any advice or similar stories, I would really appreciate hearing them.

P.S. I have to add (shamefully) I have not been getting the high 2.1s and firsts typically seen by those on rigorous economics degrees (not failing either) due to various home issues, so if this may make things impossible, please do say.