Hi,
I am on my 2nd year of my Psychology degree. To become a Psychologist you will need at least a 2.1 in your undergraduate degree.
After this it is recommended (but not essential) that you take a masters in clinical psychology to better your chances in getting into a Phd in clinical Psychology.
You will also need ALOT of experience in a care setting, paid or voluntary e.g. care home.
So long story short :
Bsc Psychology - 3 years
MSc In Clinical Psychology - 1 - 2 years
Phd In Clinical Psychology. - 3 years
Also be aware that you may not gain entry to MSc or Phd on your first go, alot of people have to keep reapplying each year as this is a VERY competitive field.