I have a BSc in Biochemistry & Molecular Biology ORDINARY degree, just because I met my fears in the middle of the 2nd year and destroyed my career. The first year I was a good student (2i average)and I started good at the 1st semester of the 2nd year but everything went wrong from that point for many reasons. The last two years I was doing an MSc in Food Safety & Quality Management (part-time) and it is expected that I will be awarded a distinction degree.
Be that as it may, my BSc being an ordinary instead of Honours is disturbing. WHAT SHOULD I DO???? Should I do my final year again? (is that possible?!) Should I study another BSc all over again in a relevant subject? Is it possible to go for a PhD with what I got right now.

You should ask your current tutors and lecturers for advice, as they will know the specific level of demand and opportunities in your area of research. I would doubt that it is possible to resit your third year after you've been away for two years (if at all). Starting another BSc will be expensive and will delay your career for another three years. If you're serious about a career in research then I would recommend applying now for jobs in a research environment. The experience gained may help in securing a PhD place at a later date.