How to fix my Samsung RS21 fridge/freezer?

Put lots of beer in the fridge for a party, and the temperature went up and down quite wildly, and the fridge made a 'phutting' sound as the door opened. Emptied it as advised and switched off for 24 hrs. Ran quite smoothly for a couple of days, then the same thing happened, and now the freezer wants to compete with the cooker. What do I need to do, as I can't find someone local to do it. Does the Samsung Repair kit work?. ie. has it done so for anyone else? Machine is three years old; it should last longer than that.