hi dharmveer,
i read your problem,your
dentist is absolutely right..............
because of lots of sweets and chocolates infection/caries has been started in your teeth............
now this infection has been reached to root which have nerves so you feel pain ..................
painkillers give you temporary relief...........
for permanent relief you should go for proper treatment............
so please follow your dentist properly and you will get permanent relief..........
nothing to get worried...........
now filling is a process in which dentist remove caries and fill that portion with appropriate material to save your remaining tooth structure...........
this is to maintain you teeth structure which are neccessary for eating, speech and esthetic/facial appearance,smile etc..........
so please follow your dentist and maintain oral hygien......
take care
Dr.Gunjan Gupta