Sam
There are too many variables for me to answer.
You say you have lost your Mobility award, did you have a Daily Living award? Was it removed as well?
If you have no Mobility award then you are no longer entitled to a reduction in your Car Tax. The DVLA have not made any definitive statement about how claimants need to deal with this situation but your car not being properly taxed can mean that your insurance is invalidated.
As to your Pension Credit and Council Tax, all I can suggest is that you put your information into one of the online benefit calculators, this should give you an indication of any issues.
www.gov.uk/benefits-calculators Gordon
