UK Car Repair: FIat punto starting prob, door locks, sidelights

Question
hi i have a fiat punto 1.1 p reg. recently i had it serviced it was fine the day i got it back after a few days where i did not drive it i went to start it but the batt was dead i noticed that the sidelights were still on but dying however all my lights were switched of. What is the problem and is there anyway of fixing it myself also would this be the garages fault as i did have the electrics on my car window looked at?  

Answer
The side lights presumably work with the alarm system, this in turn works with the door locks which of course are in the door panel!  What exactly did they do to the window? Of course it might be just a fluke, disconnect & recharge the battery then see if the lights stay ON, anoter tip is operate the remote lock and unlock a few time, this often sets the alarm parameters.