Before you pay for the doctor, you might try a few things.
#1. It sounds like you're getting a pretty decent amount of cardio exercise (walking), but why not try lifting weights? You may not have much muscle. The more muscle you have, the more calories you burn (metabolism). If you're walking, you've probably got some muscle in your legs, but what about upper body and stomach?
#2. You really need to look at your diet. What exactly are you eating? The only way to do this properly is to count calories for a little while and see exactly how many calories you're putting in your body. There are calorie calculators online that can help you. You need to find out how many calories you should be eating for your height, weight, age and activity level. Then, to lose weight, you need to eat less than that. Since a pound on your body is the equivalent of 3500 calories, if you eat 500 less each day than your body requires, you'll lose a pound in 7 days. I don't know the formula for kg.
#3. The last thing is that we all carry weight differently. You are just genetically predispositioned to have more weight in your trouble areas. You cannot spot reduce fat. You have to lose it from your whole body. But, if you eat right, get cardio exercise and lift a few weights, you can be the best you're capable of. Good luck and hope this helps!