I try running, stair climbing and stretching every day and I try not to eat to feel full up. I don’t know if this is a stupid idea, but I’m sure dieting involves feeling moderately hungry, which is what I do now.
Sometimes, after a long hard workday I feel so hungry I eat a lot for dinner, meaning I don’t have to have breakfast before I start working out. I don’t know if this is also a stupid idea. Do you have a small breakfast before starting your work out in the morning before going to work?
A variation of this involves eating only whole grains at night before going to sleep because sometimes that’s the only thing at hand.
Should I change anything?
Impossible to really answer that. Your body weight is the end result of many, many habits.
You have described only a few of your habits, and without most details. But even if we knew all, really all of your habits with all specific data, there is still no such thing as a calculator formula for the end resulting weight. Bodies act differently.
Become aware of what you are doing, stick to your changed habits (at least three weeks before reviewing any change), and then watch your weight regularly. Write things down daily, or twice a week, or weekly. Do not look for a daily success, but yearly (and maybe weekly too).