Parked car up on sat night went to start it on sunday morning and battery was dead, jump started it and drove it for about ten miles.

Parked it up again and went to start it again this morning and battery was flat but had just enought power to turn it over a few times and start but dash lights where really dim.

IS the battery covered under 1 or 3 years warrenty?

Checked the charge going into the battery when running and was 13.8 volts so alternator seems to be working

Is it just a dodgy battery?

 

get it down to halfords and just ask them to test the battery. they'l have a tester that they connect up to it and it will tell you anything thats wrong with the battery, which cell if any are dead etc. make sure its charged before you go down though. good luck.